. A-O-A117 053 UNITED STATES STEEL CORP MONROEVILLE PA F/6 11/6INVESTIGATION OF STEELS FOR I MPROVED WELDABILITY IN SHIP CONSTR--ETCIU)1981 B S REISDORF, F DORIS DOT C-06-BB-A

0*LASSIFIED_ SR-1256 SSC-305 N

~SSC-305

INVESTIGATION OF STEELSFOR IMPROVED WELDABILITY

S IN SHIP CONSTRUCTIONt PHASE IIz0

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-j SHIP STRUCTURE COMMITTEE

1981

82 07 19 171

SHIP STRUCTURE COMMITTEE

The SHIP STRUCTURE CMOWITEIE is coostituted to prosecute a researchprogram to improve the hull structures of ships ad other marine structuresby an extension of knowledge pertaining to design, sterials and methods ofconstruction.

RAdm Clyde T. Lusk, Jr. (Chairman) Mr. J. GrossChief, Office of Merchant Marine Deputy Assistant Administrator for

Safety Comercial DevelopmentU. S. Coast Guard Headquarters Maritime Administration

Mr. P. M. Palermo Mr. J. 5. GregoryExecutive Director Chief, Research & Development StaffShip Design & Integration of Planing & Assessment

Directorate U.S. Geological SurveyNaval Sea System Comand

Mr. W. H. Hannan Mr. Thomas W. AllenVice President Chief Engineering OfficerAmerican Bureau of Shipping Military Sealift Command

LCdr D. B. Anderson, U.S. Coast Guard (Secretary)

SHIP STRUCTURE SUBCOMITTEE

The SHIP STRUCTURE SUBCOMMITTEE acts for the Ship StructureCommittee on technical matters by providing technical coordination for thedetermination of goals and objectives of the program, and by evaluating andinterpreting the results in terms of structural design, construction andoperation.

U. S. COAST GUARD MILTARY SEALIFT COMMAD

Capt. R. L. Brown Mr. Albert AttermayerCdr. J. C. Card Mr. T. W. ChapmanMr. R. E. Wil1lims Mr. A. B. Stavovy

Cdr. J. A. Sanial Mr. D. Stein

NAVAL SEA SYSTEMS COMMAND AMERICAN BUREAU OF SHIPPING

Mr. R. Chiu Dr. D. LiuMr. J. B. O'Brien Mr. I. L. SternMr. 14. C. SandbergLcdr D. W. Whiddon U. S. GEOLOGICAL SURVEYMr. T. Nomura (Contracts Admin.)

Mr. R. GiangerelliMARITIME A1D4INISTRATION Mr. Charles Smith

Mr. N. 0. Hammer INTERNATIONAL SHIP STRUCTURES CONGRESSDr. W. M. MacleanHr. F. Seibold Mr. S. G. Stiansen - LimonMr. M. ToUmA

AMERICAN IRON & STEEL INSTITUTE

NATIONAL ACADEMY OF SCIENCESSHIP RESEARCH COMMITTEE Mr. X. H. Sterne - Liaon

Mr. A. Dudley aff - Liaison STATE UNIV. OF NEW YORK MARITIME COLLEGE

Mr. R. W. Ruake - Liaison Dr. W. R. Porter - Liaison

SOCIETY OF NAVAL ARCHITECTS &U. S. COAST GLAD ACADEMY

MARINE ENGINEERS LCdr R. G. Vorthean - Liaison

Mr. A. B. Stavovy - Liaison U. S. NAVAL ACADMY

WELDING RESEARCH COUNCIL Dr. R. Sattacharyys - Liaison

Mr. K. 1. Koopwn - Liaison U. S. MERCHAO T MARINE ACA1EMY

Dr. Chin-Bee Kin - Liaison

• . ... . _. -, , .

Member Agencies: Address Correspondence to:

United States Coast GuardNaval Sea Systems Command Secretary, Ship Structure Con, ,tte

Military Seift Command IU.S. Coast Guard Headquarters, -P'Tr 13,Miliary ealit Coman Washington, D.C. 2050Q3

Maritime Administration C iWUnited States Geological Survey Ructuro

American Bureau of Suipping coiixtAn Interagency Advisory Committee

Dedicated to Improving the Structure of Ships

SR-1256

1981

Much of the modernization taking place in the worldshipbuilding industry in the last decade has centered aroundthe use of new, more efficient welding techniques. The poten--tial increase in productivity with new high-deposition ratewelding processes is considerable. However, in order to takefull advantage of the benefits of the new welding practices,additional metallurgical control appears necessary for mini-mizing heat-affected zone and weld-metal property degradation.

The Ship Structure Committee is now sponsoring aproject directed toward determining the weld procedure andmetallurgical control necessary to develop adequate toughnessin the weldment, using high-deposition rate welding procedures.This report describes the second phase of that work.

Rear Admiral, U.S. Coast GuardChairman, Ship Structure Committee

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Technical Report Documentation Page1. Report No 2 G,-nren1 Ac--son N 3 Recreor $ Catalog No

SSC-305 ~ ~ /4. T,tle or'. ubthie I S r .cor ['arr

INVESTIGATION OF STEELS FOR IMPROVED WELDABILITY 1981IN SHIP CONSTRUCTION - PHASE II F6 Pefr,,,, og ..... Code

........ 8. 8P1-o,,g ......... Repor, NoB. G. Reisdorf and W. F. Dcmis SR-1256

9. P. 0 t,0 1,, J'qon-Zot.tor No. e and Add-- 0s- 1 - I)I *Intt No ' TRA! S,

U. S. STEEL CORPORATION125 JAMISON LANE DOT-CG-80588-AMON OEVILLE, PA 15146 o - 80 588A13 7 yp ft P o,, and Po oee

12 Sponnorng Ageny Norce ond Addes

U INTER.1, REPORT - PHASE IIU.S. COAST GUARDOFFICE OF MERHAT MARINE SAFETY --

WASHINGTON, D.C. 20593 ng .. Agee C,,

G-Mr- Suulerentary Note

The U.S.Coast Guard performs the contracting services for the Ship StructureCca -ttee.

16 Ahst,oct he purpose of the present three- phase investiqation is todevelop economical shin-plate steels with improved heat-affected-zone (RAZ) touohness when weled at high heat inputs. The firstphase consisted of a literature review aimed at identifying economi-cal compositions and processing methods that were expected to resultin steels having good HRZ toughness when welded at high heat inputs.-This review resrilted in the selection of 20 steels to be melted andevaluated at the Research Laboratory.

The present renort summarizes Phase II. During this phase,the 20 laboratory-melted steels were produced with compositionalvariations in the content of titanium, titrogen, vanadium, boron,calcium, and rare-earth metals. These steels were rolled toI-inch-thick plate and normalized. Thermal cycles occurrinq in the11A? near the fusion line of high-heat-input welds were simulated insamples of all these steels. On the basis of the toughness andm icrostructure of these simulated-weld samples, eight of thelaboratory-melted steels were selected for welding along withthree commercially produced ship steels. tn addition to submerged-arc (SA' welding at a typical heat input of 75 kJ/inch, two high-heat-input welding processes were used: Il) electroslaq welding (ES)at about 1000 kJ/inch and (2) two-pass SA veldinq at 180 kJ/inch perpass.

Charpy V-noteh tests of the HAZ of these steels showed thatthe steel with the best RAZ toughness for the ES weld was a calcium-treated 0.05 percent vanadium steel with a low content of residualelements (i., Cu, Cr, and Mo). Several titanium steels withoutboron and also one with boron had good HAZ toughness when ES-welded.e RA tou hness of the 0.08 percent vanadium steel and several

f the titanium steals was also good when the steels were SR-weldedat 110 kJ/inch. Nowvmr, two of the three titanium steels thatcontained boron had poor HAl toughness for a normal-heat-input(75 kW/inch) SA weld. Overall, vanadium, low-residual-elementsteels. and titanium steels without boron Appear to show promiseof providing .improved HAS toughness in high-heat-input welds.

17. Key Words 18. Distrbution Statement

Weld Rare-Earth Metals This docunent is available to the U.S.Heat Affected Zone Submerged Arc Weld public through the National TechnicalSteel Electroslag Weld Information Service, S pingfield, VAToughness Charpy V-notch 22161

19. Seturty Class,(. (of IN'S report) 10.Setw ,ty Class,). (of thr s page) 21. No. of 'Pages f22. Pr,,e

Unclassified Unclassified 50

Form DOT F 1700.7 18-72) Reproductio. of completed page authorized

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I1CIONTENTS

Introduction 1

Materials and Experimental Work 1Comrercially Produced Plates 1Laboratory-Melted Steels 1Mechanical Testing of Unwelded Plates 5Gleeble Treatnnt 5Microstructure of Base Plate and Gleeble Samples 6Welding Procedures 6CVN Testing of Weldnmts 8Hardness Traverses of Weldments 8Weld-HAZ Microstructure 8

Results and Discussion 10Base Plate 10Gleeble-Treated Steels 10Effect of Chemical Composition on the Toughnessof Gleeble-Treated Samples 13

Welded Steels 26Toughness of eldments 26Ccoparison of Toughness of Weld HAZ with Gleeble-Treated Samples 29

Microstructure of Weldments 31

Conclusions 31

References 37

APPENDIX A Individual Transverse Charpy V-NotchTest Results from the Investigated Plates 38

APPENDIX B Individual Charpy V-Notch Test Resultsfrom ES-Weld-Simulation Gleeble Samples 39

APPENDIX C Individual Charpy V-Notch Trest Resultsfrom SA-Weld-Sixnulation Gleeble Samples 40

APPENDIX D Individual Charpy V-Notch Data forElextroslag-Welded Steels (1000 kJ/in) 41

APPENDIX E Individual Charpy V-Notch Data forSubmerged-Arc-Welded Steels (180 kJ/in) 42

APPENDIX F Individual Charpy V-Notch Data forSubmerged-Arc-Welded Steels (75 kJ/in) 43

APPE74DIX G DPH Hardness of Butt-Welded JointsInvestigated 44

y

Introduction

The purpose of the present project is to develop economicalship-plate steels having improved heat-affected-zone (HAZ) toughnesswhen welded with high-heat inputs. Phase I of this project con-sisted of a literature search for steels that were reported to haveimproved HAZ toughness when welded with high-heat inputs or whenheat-treated to simulate the thermal cycle in a weld HAZ. Theliterature search also identified steels that had high grain-coarsening temperatures and that should, therefore, have a narrowcoarse-grain weld HAZ. On the basis of this literature search, 20steel compositions were selected for melting and evaluation at theResearch Laboratory. The results of the literature search, thereasons for the selection of the various steel compositions, anddetails of the testing program were presented in the report1 ) onPhase I of this project.

During Phase II~the 20 laboratory-melted steels were pro-duced, and three commercially produced ship-plate steels wereobtained for comparison. The thermal cycles occurring in the HAZadjacent to the bond line were reproduced in samples of all theinvestigated steels by using a Gleeble machine. On the basis ofthe toughness results and microstructures of these Gleeble-treatedsamples, eight steels in addition to the commercially producedplates were selected for welding with typical and high-heat inputs.The effects of the various alloying additions on the HAZ toughnessand microstructure were determined. Details of Phase II arecontained in the present report.

Materials and Experimental Work

Commercially Produced Plates

Three one-inch-thick (25 mm) plates of commercially producedship steels were included in the present program as referencematerials. One plate was a calcium-treated ABS V-051 steel producedby Lukens Steel Company. The second plate was Nippon SteelCorporation's HT-50S Class D plate developed for one-pass (highheat input) submerged-arc welding. The third plate was ADS CSsteel proiuced by U. S. Steel Corporation (USSC). All ofthe plates were received in the normalized condition.

Laboratory-Melted Steels

Table I shows the aim chemical composition and plate checkanalyses of 20 laboratory-melted steels. These 500-pound (227 kc)

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7- by 12- i, 24- inch (178 by 305 by bl mm) ingot molds. All theingots were cooled to room temperature. Si.teen of the 20 ingotswere toheated to 21501F (1290*C) anih rolled in the 24-inch directiolto 5-inch-thick (127 mm) slabs, which were air-cooled to roomtemperature. These slabs were reheated to 2350°F and rolledlongitudinally to 1-inch-thick plate in 12 passes of about 13percent reduction per pass with a final-pass temperature of 1900OF(10401C) as measured by an optical pyrometer.

As discussed in the report I ) on Phase I of this project,the literature indicates that to produce the fine titanium nitrideparticles that restrict grain coarsening, the cooling rate of theingot down to 2010*F (1100*C) must be fast enough (29*F or 5*C perminute) to prevent the formation of coarse titanium nitride particles.Furthermore, some investigators state that the steel must not bereheated more than once above about 2000OF (1095 0 C). Cooling ratesfor slabs from continuous casters exceed this specified coolingrate and so do those for the small laboratory-melted steels in thepresent investigation. Continuous-cast slabs are generally heatedonly once for rolling to plate, so the titanium nitrides should notcoarsen; whereas ingots, or at least the outer and cooler portionsof ingots, are generally reheated twice above 2000*F-once forrolling to slab and once for rolling to plate.

In the present investigation, four steels containingtitanium, Steels 12, 13, 14, and 15, were processed in a mannerthat simulates the commercial production of plate from continuous-cast slabs. That is, these four ingots were reheated only once androlled directly to plate. The heating temperature was 2350 0 F, andthe ingots were rolled straightaway to 1-inch-thick plate in 15passes of about 12 percent reduction each, with a final passtemperature of 1900'F. Several other titanium-containing steelsshown in Table I (Steels 11 and 16 through 19) were among the 16steels reheated twice for rolling, but according to the literature,other elements present in addition to the titanium (calcium and/orrare earth metals) permit such processing.

2 ,3 )

Fight laboratory-melted steels were calcium treated. Inproduction, calcium is often injected as a calcium silicide powderwith an inert-gas carrier. The usual purpose of the calciumaddition is to reduce the sulfur content of the molten steel and toform sulfides that are hard and do not string out at the plate-rolling temperature. Additionally, calcium was added to some ofthe laboratory-melted steels containing titanium-steels 16 through19-because it is claimed 2 ,3) that fine calcium-containing precipi-tates form and act as nuclei for the p,.cipitation of titaniumnitride, which retards grain coarsening.

4

As equipment to inject a calcium powder was not availableat the Laboratory, cannisters containing a 20 percent calcium and80 percent iron proprietary additive were secured to the end of arod and plunged into the ladle. Because the reaction of calciumwith the molten steel is hiqhly exothermic, the calcium additionwas made in three separate plunges to prevent the reaction fromexpelling the additive from the ladle. The total amount of calciumadded would have amounted to 0.027 percent in the steel if nonewere lost.

Plate rolled from the first trial showed that the calciumaddition was only partially effective in balling sulfides-somewere strung out, some were short, and some were balled. Therefore,two more trials were made, one with the calcium silicide oftenused for production of commercial heats, and one with twice as muchof the aforementioned calcium-iron additive. Sulfides in the platefrom these two trials were also only partially balled and theinclusion content of these steels was undesirably greater.Therefore, the first of the above-described practices was used inmakinq the eight calcium-treated steels.

The plates from the laboratory-melted steels were normalizedby treating them in a 1675OF (913 0 C) furnace for one hour and aircooling them.

Mechanical Testing of Unwelded Plates

Eighteen transverse Charpy V-notch (CVl.) specimens andduplicate 0.357-inch-diameter (9.07 mm) tension-test specimenswere machined from the quarterthickness of each of the plates. TheCVN specimens were tested over a range of temperatures to establishtransition behavior and the tension-test specimens were tested atroom temperature.

Cleeble Treatment

Before the Gleeble could be used to simulate the thermalcycles that occur in the HAZ near the fusion zone, it was necessaryto determine the time-temperature cycles for the high-heat-inputwelding conditions that would be used in this study. Therefore,time-temperature measurements were made in an ES and in an SAweldment with embedded thermocouples. Because the ABS-specifiedlocation for Charpy V-notch testing is the plate quarterthickness onthe last-pass side of a weldment, the thermocouples were placed atthis position. As the location of the bond line could not beprecisely predicted, seven thermocouples were used; one was placed

5

at the expected location of the bond line, and three were placedon each side of the center thermocouple at 0.030-inch (0.75 mm)increments from the expected bond-line location.

The hiqhest temperatures recorded for surviving thermo-couples in the weldments were 2525*F (1385*C) for the ES weld an-,2545*F (1396'C) for the SA weld. The data from this experiment areshown in Table II and were used in the Gleeble simulations, exceptthat a peak temperature of 2525*F was used for both weld simulatcnsso that differences caused by the two treatments would reflectdifferences in heating and coolinq rather than differences in anarbitrarily chosen peak temperature. The location of this peavtemperature in the HAZ is only a fraction of a millimeter from thebon- line. A peak temperature of 2525'F was chosen rather than2462*F (1350 C), as often reported in the literature for HA?simulations, because for the high-heat-input welding conditions use'in this study, the location in the HAZ that had a peak ter-pertur,of 2462'F was outside the very-coarse-grain region for the steelused in these trials.

Twenty transverse oversize CVN specimen blanks were machinedfrom each of the 23 plates. Ten blanks from each plate were treatedwith the Gleeble by using one of the thermal cycles shown inTable I, and the other 10 blanks from each plate were treated inaccord with the other thermal cycle except that a peak temperatureof 2525'F was used in both instances. The CVN specimens machine-3from these blanks were tested over a range of temperatures todetermine transition behavior.

Microstructure of BasePlate and Gleeble Samples

Samples of the plates were examined with a light microscope.The microstructure of all the plates consisted of ferrite andpearlite. Ferrite grain size and pearlite content were determinedwith a Quantitative Television Microscope.4 ) In addition, lightmicrographs of the Gleeble-treated specimens from each steel wereprepared to show the prior austenite grain size and resultinqmicrostructure.

Welding Procedures

In addition to the three commercially produced plates andthe base steel from the laboratory heats, seven of the more promisinlsteels were welded and evaluated. These seven steels were selectedon the basis of the CVN test results from the Gleeble-treatedsamples, the microstructure of these samples, and a considerationof the alloy system to which the steels belonged.

6

Table II Teperature ?Iasurements in WeldHeat-Affected Zones

180 kJ/in.

Electroslag Weld Submerged-Arc Weld

Time, Temperature, Time, Temperature,

sec OF sec OF

0 75 0 192600 500 4 232660 1000 9 2545

690 2100 13 2505700 2525 17 2381708 2522 22 2232712 2484 26 2090717 2443 31 1965

721 2402 35 1843725 2322 39 1730729 2278 43 1632734 2227 48 1550742 2148 52 1483759 2042 56 1428768 2003 60 1380

776 1922 69 L301785 1843 77 1241802 1716 86 1195819 1602 94 1160

836 1502 103 1133853 1414 112 1104874 1320 125 1052899 1231 134 1019933 1133 146 973971 1046 168 915

1024 950 180 8841066 869 205 8311125 773 222 801

1185 695 266 7381245 627 387 6241305 574 498 5521365 527 618 4981425 490 679 475

7

All welds were made in a longitudinal direction. Platesamples of each of the 11 steels were ES-welded at a heat input ofabout 1000 kJ/inch (40 kJ/mm) and SA-welded in two passes at aheat input of 180 kJ/inch (7.1 kJ/mm) per pass and in six passes ata more typical heat input of 75 kJ/inch (3.0 kJ/mm). The jointconfigurations and weld parameters are shown in Figure 1 andtypical chemical compositions of the electrodes are given inTable III.

CVN Testing of Weldments

For the commercially produced plates, CVN specimens weremachined from the weldments in accordance with ABS and USCCqualification requirements. The CVN specimens were machined fromthe plate quarterthickness perpendicular to the weld direction withthe notch normal to the plate surface and located at the center ofthe weld, at the bond line, and in the HAZ at distances of 1, 3,and 5 mm from the bond line, Figure 2. Because the bond line wasrarely perfectly perpendicular to the plate surface over the entirethickness of the CVN specimen, different portions of the notch weregenerally at different distances from the bond line. Twelve CV!,specimens were machined from each of the five test locations andtested in triplicate over a range of temperatures to determinetransition behavior.

For the laboratory-melted steels, tests were conducted orlyon C%1N specimens machined with the notch at the bond line and the1- and 3-mm positions within the HAZ, but quintuplicate tests wereconducted at 0 and -40*F (-18 and -40*C) for each of these threelocations.

Hardness Traverses of Weldments

Diamond pyramid hardness measurements were made at theplate quarterthickness in the center of the weld, in the base plate,and in the HAZ at distances of 1 and 3 mm from the bond line.

Weld-HAZ Microstructure

Light micrographs of the HAZ from each of the 11 steelsselected for welding were prepared showing the microstructure atthe plate quarterthickness at magnifications of 50X, 200X, andlOOOX.

Table III rjpical Electrode C(bposion--Percent

Welding

Electrode Process C Mn Si Cr Ni Mo Cu

Armco WI8 Submerged-arc 0.15 0.67 0.17 0.06 1.80 0.16 0.25

Linde Mi-88 Electroslag 0.06 1.65 0.35 0.25 1.50 0.40 -

Note: Above is filler metal manufacturer's data.

SUBMERGED.ARC JOINT

i16/R.O.

STEEL & Cu BACKUP

NORMAL-HEAT-INPUT SAW NIGH-NEAT'INPUT SAW

ARMCO WI, ELECTRODE ARMCO WIS ELECTRODELINCOLN M FLUX LINCOLN $S0 FLUXo AMPERES CURRENT AMPERES CURRENT

32 VOLTS 30 VOLTS15.1 IPM TRAVEL 8 IPM TRAVEL6 PASSES-75 KJ/in. EACH 2 PASSES-IS0 K/in. EACH

ESW JOINT

LINDE MISS ELECTROE 37 VOLTSI.INE MII EECTOCE120 1PM WIRE SPEED

LINDE 124 FLUX I PS i00 KfnEA450 AMPERES CURRENT 1 PAS-I.OO ,.DI,. EACH

Figure I. Joixt configuration and Weldparameters used in currentinvestigation

----- -------- 1 \ / H-------T

NOTCH LOCATION a - CENTER OF WELDb - FUSION LINEa - HAZ. I om FROM FUSION LINEd HAZ, 3 mm FROM FUSION LINEa HAZ. 5 mm FROM FUSION LINE

Figure 2. Schematic of Notd location forCVi inpact specimens

9

Results and Discussion

Base Plate

The tensile properties and CVN transition temperatures ofthe plates investigated are shown in Table IV, and individual CVN

test results are given in Appendix Table A. Steel 4 is the basesteel in the present study, and its chemical composition was chosento provide a yield strength of about 50 ksi (345 MPa). The C%7

15 ft-lb (20J) transition temperature (V1 5 ) of Steel 4 was -150OF(-100°C) and its 50 percent shear-fracture-appearance transitiontemperature (V50 ) was -15OF (-25°C).

As will be shown subsequently, the only laboratory-meltedsteels in this investigation that showed significant improvementsin HAZ toughness were those that contained titanium (Steels 11through 19) and one steel that contained vanadium (Steel 7).Table IV shows that, as a group, these titanium steels had base-metal toughness considerably inferior to that o" the titanium-freesteels. The base-metal toughness of the vanadium steel, Steel 7,however, was about the same as that of the reference steel.

The microstructure of all the plates consisted of ferriteand pearlite. As Table V shows, the ferrite grain size of all thesteels was fine, ranging from about ASTM No. 8 to 10. Becauseof the low-carbon content of the steels, the pearlite content wasalso low, ranging from 12 to 23 percent.

Gleeble-Treated Steels

Individual CVN test results from the Gleeble-treatedspecimens are shown in Appendix Table B for the ESW simulation anOin Appendix Table C for the 180 kJ/inch SAW simulation. Table VIshows the average CVN energy absorbed at 00 F (-180 C) and -40OF(-40*C) for each of the steels.

Table VI also shows the Rockwell B hardness of the Gleeble-treated samples. No significant correlation between hardness andtoughness of these samples is apparent.

Light micrographs of all the Gleeble-treated steels wereprepared at a magnification of 50X to show the prior austenitegrain size and at 200X to show finer details of the microstructure.Prior austenite grain-size ratings for these samples are given inTable VI. In many instances, particularly for the coarser grainsamples, the prior austenite grain boundaries were outlined by acontinuous network of ferrite so that the grain size was welldefined. For some samples, the prior austenite grain boundarywas less distinct and, in a few instances, unratable.

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Effect of Chemical Composition on theToughness of Gleeble-Treated Samples

For this discussion, the toughness values of Steel 4 (thebase steel) shown in Table VI (12 ft-lb at 00 F for ESW and 8 ft-lbat 0*F for SAW) will be used for comparing the toughness of theother nleeble-treated steels. For the remainder of this discussionof composition, to avoid constant repetition of "toughness of theCleeble-treated steel," the following comparison refers only toGleeble-treated steels and their toughness values shown in Table VI.

Steel 1. This steel was considerably better than Steel 4for the SAW simulation (28 versus 8 ft-lb at 00 F) and somewhat betterfor the ESW simulation. The major differences in composition betweenthese steels are that Steel 1 contains columbium and Steel 4 containsresiduals and higher nitrogen.

Steel 2. The toughness of this reference steel was consid-erably better than that of the base steel for both weld simulations.Steels 2 and 4 are similar except that Steel 2 contains lowernitrogen, higher sulfur, and no residual-element additions.

Steel 3. The toughness of this 0.023 percent sulfur steelwas not significantly different from that of the 0.007 percentsulfur base steel.

Steel 5. The addition of calcium to this steel did notimprove its toughness compared with that of Steel 4.

Steel 6. The differences between Steels 6 and 4 are thatcalcium and columbium were added to Steel 6 and the residualelements (Cu, Ni, Cr, and Mo) present in Steel 4 were not added toSteel 6. These differences did not result in any significantdifference in toughness. A puzzling result is that the toughnessof Steel 6 was lower than that of reference Steel 1 which has avery similar composition.

Steel 7. This calcium-treated, vanadium, no-added-residualsteel had improved toughness especially for the ESW simulation(35 versus 12 ft-lb at 0°F).

(Text continued on page 25)

13

" ' . . .. . | 1 1 It I , ,l , , I I,. ... .... . , . .. .

A.

Glee-I lo-tjeatcod

samples ()f Steel ,I.and;~A Iea :.. ~i.in,~

mv~i

IRY,~t w. 4c.

I'-VW I C Q

itaMr

7. 0 ,

B-Gleeb&le simuldation D 1800 10 inc A vlSW 180 kT/'inc. IA.wi

14~

Figure 4. -icrographs ofl'ileeble-treatedand %eldedsamples of Steel7.Nital Etch. 40X. -

C. 75 kJ/inch SAW weld

H-A/weld

0 li

-- s X0

L~' '~

A. Gleeble simulation D. 180 kJ/inch SAW weldSAW 180 kJ/inch. HIAZ/weld

4?~~

A .

TV

... .....

B. GLe e b Ie simulation E. 1000 kjr'inci, FS weldLSW 1000 LJ1 "inch. 15

dczI4\re Id

Figure 5. Micrographs of NGleeble-treated -

and welded 14r~

samples of Steel 11. ~.~Nital Etch. 40X.

vl4

C. 75 IC/inch SAW weld

HIAZ/weld

nn e

4

A. Gleeble simulation D. 180 I/inch SAW weldSAW 180 IC/inch. HAZ/weld

B3. Gleeble simlation E. 1000 IC/inch ES weld[SW 1000 IC/inchi. 16

:A2/w.eld

- ac ki ~ icrographis ofGleeble-treated.

and weldedsamples of Steel 12.Nital Etch. 40X.

C. 75 kJ/inch SAW weld

f AZ/iAeld

Gleeble simulation D. 180 kJ/inch SAW we-ldSAW 180 kJ/inch. HAZ/weld

.x i **.

.,*4if

*,,,'Till'

ii. leele smultio E. 000kj/ncl- ESvel

-SW 10 0 Oh n .1

:AZ:e

Fue 7. Micrographs of A'1.Gleeble-treated Kand welded ~~_samples of Steel 15.

C. 75 kJ/inch SAW weld

HAZ/weld

~--A

'12 1-1,4-. -

A. Gleeble simulation D. 180 kJ/inch SAW weldSAW 180 kJ/inch.

HAZ/iveld

Irv 4..I2 --

B3. Gleeble sirmilation E. 1000 kJ/inch . S weldESW 1000 kJ/inch. 18

AN/..,1

F igure 7. Micrographs of4Gleeble-treated-anid veldedsamples of Steel 15. *. '"'

Nital Etch. 40X. .-

.LA

C. 75 kJ/inch SAW weld

FHAZ/ld

-'AA

~O

A. Gleeble simulation D. 180 kJ/inch SAW weldSAW 180 kJ/inch LA/wl

HA$ vl

-z'

B. Gleeble simulation E. 1000 kJ/ilci- ES weldLSW 1000 kJi/inch. 18

1UAZ/x'eld

Figure 8. Micrographs of tj ~rq '~-

Gleeble-treated ~~arnd weldedsam-ples of Steel 17 . .Nital Etch. 40X. %4

C. 75 kJ/mnch SAW Aeld

HAZ/weld

-a-q

IN

SA 80k/ic. HA/wl

.4%

#' -*~s

A.Gleeble simulation E. 1800 IC/inc- S weldSW 180 kJ/inch. 19/wl

Figure 9. 5Acrographs ofGleeble-treateiand we .dedsamples of Steel 18.Nital Etch. 40X..

C. 75 IC/inch SAW weld

iAZ' weld

A . .lel simulatio D.. 180 kJic S.. weld ~'~SAW* 18 Jic. A wl

B. Gleeb K sndtin E.- -00 M/ . S el

ESW 1000 'Jinh.2

4 Y4

and welded C~'4

samples of Steel 1.t-YX~ssNital Etch. 40X. 'e:-"

C. 75 kJ,'mch StA- mwoIkL

iIZ td

47, 6

-kV,

PA4'~ ~ .~ t ~IA,

i3. l;eelec simulation D . 180 1-J/i;nc AIv'AlS 180 <U inch. 21ve

La7/\eld

Figure 11. Nicrcxjraphs of -

and we-1ded. tsamples of St tel t.Nital Etch. 40X. A

C. 75 IC/inch SAW weld

HAZ/weld

& W,

M. -4 AT

k..3&.

ir Glei .iuato E.10 .7nh Swl

*S 1000. kC-n.2

{4k

Fiqiure 12. M-icrograplisGleeble-treatcW-.-I j

and %eldedtsamples of S teel1

Nia Etc 1h 7N .l

CAZ/~d

ilzwl

-i l ,

A. Gleeble simulation D. 180 kJ 'inch SAW xld

SAWv 18 0 ki/in-i ~Ix~ 'weld

4,, ;z

A- A -w;Ola-'A'K

B .Gleeble simiulation F.I~nr)

ISW 1000 W,, i nch.2

samlples of Steel 1N ital Etch, 10%X. .. ... 'A

C. 75 MU inch qAW webI

I 1A2 1 'eld

7 IT' ,

A Gleeble simuliation D 180 RJ'/inch SAW weldSAW 18 0 1-0C inch.

I IAZ/weld

Al~.*.

t --.

VCt

B.Gebe-mdto .E 100Iinh14 \,

ill ~ A 4's-" a,1W$2 Q .o TiLL24

Steels 8, 9, and 10. Steels 8, 9, and 10 did not show anytoughness improvement over Steel 4 for either weld simulation.All three steels contained rare-earth-metal (REM) additions, andthe total REM content of the steels was approximately twice thecerium content shown in Table I. The REM additions to these steelswere effective in balling the sulfides. Steel 8 also containedcolumbium but had no added residuals. Steels 9 and 10 containedboron.

Steel 11. This steel contained titanium in addition to aboron and REM addition. Steel 11 had about the same toughness asthe base steel for the SAW simulation, but was better than thebase steel for the ESW simulation (26 versus 12 ft-lb at 00 F).

Steels 12, 13, 14, and 15. These four titanium steels wereheated only once for rolling, whereas all the other laboratory-melted steels were heated twice. All four steels showed someimprovement over the base steel but Steel 15, which containedboron, was considerably better than Steels 12. 13, and 14, particu-larly for the ESW simulation. For this simulation, Steels 12, 13,14, and 15 absorbed 16, 18, 12, and 34 ft-lb, respectively, at 0°F.Steel 14, which contained about twice as much titanium and nitrogenas Steel 13 but otherwise had the same nominal composition, hadpoorer toughness than Steel 13 for the SAW simulation. Thedifference in aluminum content between Steels 12 and 13 (0.012versus 0.030%) did not result in any significant difference intoughness.

Steels 16, 17, 18, and 19. These four steels all hadcalcium additions, contained titanium, and were reheated twice forrollinq. Steel 18 was REM-treated, and Steel 19 contained boron.All four of these steels had considerably better toughness than thebase steel for both weld simulations and, overall, the boron-containinq steel was the best of this group, as was the boron-containing steel in the group of Steels 12 through 15. Even thoughthese steels were heated twice above 2000 0 F, their toughness wasgenerally good. However, because none of the steels that wereheated once had the same composition as those heated twice, noconclusion can be drawn as to the effect of reheating twice.

Steel 20. This steel did not have residual elements added,had a low silicon content (0.05%), and contained vanadium and boron.This steel had better toughness than the base steel and somewhatbetter toughness than the other vanadium steel in this investiqation(Steel 7) for the SAW simulation, but it was not nearly as tough asSteel 7 for the ESW simulation (18 versus 35 ft-lb at 00 F).

25

Steels L, N, and U. Neither Steel L nor Steel U wassignificantly better than the base steel except that Steel U wassomewhat better than the base steel for the SAW simulation (16versus 8 ft-lb at 0°F). For the SAW simulation, Steel N was thebest steel investigated, but for the ESW simulation many of theother steels in this investigation were better. This commercialsteel is recommended by its producer for high-heat-input SA weldsbut not for ES welds.

Welded Steels

Primarily on the basis of the toughness of the Gleeble-treated samples, and to a lesser extent of the microstructure andalloy system to which the steels belonged, eight laboratory-meltedsteels (Steels 4, 7, 11, 12, 15, 17, 18, and 19) were selected forwelding in addition to the three commercially produced steels.These 11 steels are identified in the last column in Table VI.Although Table VI shows that Steels 1 and 2 had good toughness,these steels are laboratory-melted versions of commercial steelsand were included in the investigation for information only; theywere not part of the alloy investigation and thus were not selectedfor welding. Although the Gleeble-treated samples of Steel 4 didnot have good toughness, it was the base steel in this study andwas welded for comparison. Steel 16 had good toughness but wasnot welded because Steel 17 had somewhat better toughness andbelonged to the same alloy system (Ti-N). The toughness values ofthe Gleeble-treated samples of Steel 11 were not very good but themicrostructure of these samples was very fine and it was selectedfor that reason.

Toughness of Weldments

Each of the 11 steels selected for welding was ES-weldedat a heat input of about 1000 kJ/inch and SA-welded at heat inputsof 180 and 75 kJ/inch. Individual CVN test results obtained fromthese weldments are given in Appendix Tables D, E, and F for theES weld and the 180 and 75 kJ/inch SA welds, respectively. AverageCVN energy absorbed at 0°F (-18°C) and -40*F (-40*C) for tests atthe fusion line and 1- and 3-mm HAZ locations are shown inTables VII, VIII, and IX for these three welding processes. Parent-plate-toughness values are also shown in these tables for comparison.For each of comparison, the results from Tables VII, VIII, and IXfor the 1- and 3-mm HAZ locations are shown in Table X.

ES Weldments. Referring to Table X it is apparent that thebase steel (Steel 4) had the poorest toughness at the 1-mm testlocation of all the laboratory-melted steels that were ES-welded.

26

Table VII Charpy V-Notch Impact Propertiesof ESW Joints Investigated (heatInput of Approximiately 1000 ]J/in)

Energy Absorbed, ft-lbat 0*F at -40F

Steel Plate FL* I mm 3 mm Plate Ft I mm 3 mm

4 105 11 12 46 76 11 6 41

7 106 28 63 62 76 13 33 60

11 110 29 29 64 20 13 9 24

12 65 20 38 46 44 21 18 27

15 65 26 35 41 31 9 16 21

17 81 22 53 51 55 29 1" 15

18 226 36 65 87 137 19 14 31

19 52 42 45 50 24 13 35 44

N 121 65 44 91 96 34 8 70

L 163 32 9 7 133 10 5 8

U 40 27 24 30 25 20 11 16

Fusion line.

Table VIII Charpy V-Notch Impact Propertiesof SAW Joints Investigated (eatInput of 180 kJ/in)

Energy Absorbed, ft-lbat 0F at -40*F

Steel Plate FL 1 mm 3 mn Plate FL 1 mm 3 'm

4 105 29 29 34 76 15 16 24

7 106 48 55 85 76 16 19 66

11 110 45 47 39 20 29 19 22

12 65 67 49 57 44 38 35 43

15 65 50 40 44 31 24 25 21

17 81 51 54 62 55 19 22 44

18 226 60 47 68 137 15 18 34

19 52 62 51 49 24 39 24 29

N 121 53 51 91 96 21 21 57

L 163 34 20 71 133 14 10 46

U 40 37 28 27 25 29 16 20

Fusion linp.

27

Table IX Charpy V-Notch Impact Propertiesof SAW Joints Investigated (HeatInput of 75 IJ/in)

Enercv Absorbed. ft-lbat O*F at - 40OF

steel. P.l~t FL* 1 an 3 mm Plate FL I nm 2 mm

4 105 53 69 73 76 34 26 44

7 106 120 101 100 76 49 52 78

11 110 81 76 28 20 65 23 8

i: 65 74 68 61 44 43 50 45

65 66 59 43 31 45 37 33

17 81 100 89 59 55 71 66 43

18 226 121 133 117 137 89 75 63

19 52 74 49 16 24 52 42 8

N 121 109 112 108 96 76 76 89

L 163 77 138 141 133 25 132 115

U 40 44 42 35 25 44 40 33

"Fusion line.

Table X Conparison of HAZ Touglhess for the Three Welding ConditionsInvestigated

CVM Eneray Absorbed. fe-lb0___________________________-40"7

MinJium Velue Minimum ValueESW SAW 180 J/in. SAW 75 Wi/in, for any Weld and ESW SAW SOkJ/in. SAW 75 kj/in. for any Weld and

Steel I m 3 m I m 3 - m 3 m EiCher Position I u 3 m 1 m 3 mm I am 3 m Either Position

4 12 46 29 34 69 73 12 6 41 16 24 26 44 67 63 62 55 85 101 100 55 33 60 19 66 52 78 1911 29 64 47 39 76 28 28 9 24 19 22 23 8 812 38 46 49 57 68 61 38 18 27 35 43 50 45 1815 35 41 40 44 59 43 35 16 21 25 21 37 33 1617 53 51 54 62 89 59 51 17 15 22 44 66 43 1518 65 87 41 68 133 117 47 14 31 10 34 75 63 1419 45 50 51 49 49 16 16 35 44 24 29 42 8 8N 44 91 51 91 112 108 44 8 70 21 59 76 89 8L 9 7 20 71 138 141 7 5 8 10 46 132 115 5U 24 30 28 27 42 35 24 11 16 16 20 40 33 11

28

These toughness comparisons will be based on the 1-mm locationrather than the 3-mm location because this location generallyhas poorer toughness for the high-heat-input welding processes.The two steels with the best toughness at -40OF (-40°C) for theI-mm position were Steels 7 (vanadium steel) and 19 (titanium-boronsteel). It should be noted, however, that at the -40OF testtemperature the base-plate toughness of the vanadium steel was abouttriple that of the titanium-boron steel. Four other titanium steels(12, 15, 17, and 18) had considerably better toughness than that ofthe base steel at the 1-mm location.

180 kJ/inch SA Weldments. All the laboratory-melted steelshad reasonably good HAZ toughness for the 180 kJ/inch welds, asshown in Table X. Steels 7 and 19, which had the best HAZ tough-ness for the ES weld, had good HAZ toughness for this weld, butwere not the best. The highest toughness steel at -40°F (35 ft-lb)for this weld condition was Steel 12, the titanium steel that wasonly reheated once for rolling.

75 kJ/inch SA Weldments. All the steels welded had goodHAZ toughness for the 75 kJ/inch heat input SA welds exceptSteels 11 and 19 at the 3-mm position. Both these steels containedtitanium and boron. The low toughness of Steel 19 at the 3-mmposition would be a serious deterrent to the use of this titanium-boron steel even though it had very good HAZ toughness when ES-welded because any steel selected for high-heat-input welding shouldalso be suitable for more typical heat inputs.

Hardness of Weldments. Hardness measurements were made inthe base plate, weld metal, and the I- and 3-mm locations in theHAZ for all the weldments, and are shown in Appendix Table G. Nocorrelation was found between HAZ hardness and toughness.

Overall HAZ Toughness for all Welding Conditions. To beusable for ship construction, a steel must be weldable under typicalheat inputs. In Table X, minimum CVN energy values for 0 and -40°Ftest temperatures for any of the three welding conditions are shown.The steel having the highest toughness (19 ft-lb) for its worsttest location is Steel 7. For the -4n°F test temperature, fourtitanium steels-Steels 12, 15, 17, and 18-are nearly as tough(14 to 18 ft-lb).

Comparison of Toughness of WeldHAZ With Gleeble-Treated Samples

Table XI shows results of CVN tests of Gleeble-treatedsamples side-by-side with results from weld HAZ CVN tests at the1-mm position. Actually, the thermal cycles of the Gleeble-treatedspecimens are representative of a zone closer to the fusion line

29

CU

0

-4 E

r-4

-i -4-r4-.

Lo -4

00

-P U)

10 4)z~ (1)9 -

4J 4-4

L 0 %D

Ef( 1 4

,-4

4, 4

4)

0

-4

00 a) C4 Vl% D-0mm % 4f-4 M N-4M Mr, L (n -4 0

E U

4) 4)

30

than 1 mm, but fusion-line test specimens from the weldmentsgenerally extend into the weld metal so that the 1-mm locationtest specimen would be expected to be more like the Gleeble-treated specimens.

Considering the scatter in the data, which is apparent inthe Appendix tables where individual test results are reported,the results shown in Table XI for the ES weldment and the Gleeblesimulation are surprisingly close. For the SA weld, the resultsfor the two techniques are not nearly as close, and usually theweldment tests yielded higher toughness values. This poorer agree-ment between weldment tests and Gleeble samples is to be expectedbecause of the geometry of the fusion zone in this two-pass weld,which was never perpendicular to the plate surface at the notchlocation. An example of the position and length of the notch ina CVN specimen at the 1-mm HAZ location is shown in Figure 14B fora typical 180 kJ/inch SA weld used in this investigation. Figures14A and 14C are typical weldments for the 75 kJ/inch SA and ES weldconditions.

Microstructure of Weldments

Micrographs of the HAZ region of the weldments are givenin Figures I through 13 (C, D, and E) for each of the 11 steelswelded. In each micrograph of the weldments, the weld metal is on

the right side and the bond line is about one-half inch from theright side of the micrograph. Generally, the micrographs of the

Gleeble-treated samples show a microstructure similar to that in

the weld HAZ near the bond line.

Finer details of the microstructure in the HAZ are shownin Figure 15 for the ES weldments and in Figure 16 for the 180kJ/inch SA weldments. The HAZs of several of the weldments containnumerous small grains of martensite, examples of which are indicated

by the arrows on the micrographs of Figures 15A for Steel 4 and 15C

for Steel 11. Although the HAZs with large amounts of the martensite

tend to have poorer toughness than the martensite-free ones, thecorrelation is not very strong. For example, Steel 19, when

SA-welded, had a considerable amount of martensite in the HAZ, as

shown in Figure 16H, but the HAZ had good toughness.

Conclusions

Steel 7, the calcium-treated 0.08 percent vanadium steel

with low residual content, appears to have the best combination of

HAZ toughness and base-plate strength and toughness. For CVN tests

at 0F (-180C) this steel had the best, or nearly the best HAZ

-U

lfIml PcSit-ofllnotCli ill C

,;pcciWmfl at.

t., 4 tllicknc-sS-

I~ ~~ A wwd 1(.8Ok ic

3 -urc 4 ICloqrW*,114 of iC~ )oim ts for th ~ ~ welding

rnlti1 l

-, *,A>,

S,,,

A. Steel 4 D. Steel 12

1 .., . .- ' . ,J --"--j --- ,

A. Steel 4 . Steel 12

-; k

B. Steel 11 E. Steel 15

-* " " " .f " " " " -

Figure 15" "", :.i,:,,grap,, of th I'I.,, ofte-.wlhn

C. Stee l E F. 33

Figure 15 [ticrographs of the HA Z of thze ES-weidnents.Nita! Etch. 800X

33

G. SteelL

, ., /' -. - . -' .

A/

\ r 9 1 '¢ ' i, _ " - '

H. Steel 19 J.. Steel L i

/ , : , -'".' •I " e ''-

I. Steel N K. Steel U

Figure 15 ticrographs of the HAZ Of the ES-eldMets.ital Etch. 800' (Continued)

34

Steel 4 D. Steel 12

.p

B. Stee 7*2 E.Sel1

N,#, .0 . l "

V

C. Steel 7 F. Steel 12.. -. -, .-:+1. ,

Figure 16 Uiicrograph s of the HAZ of the 180 huT/inch, SA--lx %nbents.Nital Etch. 800X.

35

, 4 ; . . ". " ".'

G. Steel 18

'~

Co..-.

..-

H. Steel 19 J. Steel L

4 . • . .

I Nita Etch 1000

t yo

I'

Nia Etch. 80.OX.

, 36

i.~.. .....

_ ,, , ',.,._r-_j ..., ... .

toughness for all three welding conditions used. Furthermore, thebase-plate strength and toughness of this steel were substantiallybetter than those of any of the titanium steels studied. The

literature has indicated that vanadium in amounts in excess of about0.10 percent had detrimental effects on HAZ toughness 5 ,6 ) and that

about 0.06 percent vanadium may have a slightly beneficial effect.6 )

Consequently, the very good HAZ toughness of Steel 7 was unexpected.The improved toughness of Steel 7 compared with the base steel mayhave resulted from its lower hardenability, which in turn resulted

from the near absence of copper, nickel, chromium, and molybdenum in

this steel (about 0.5% in the base steel).

Several of the titanium steels had very good HAZ toughnessfor all three welding conditions used. Two of the three titaniumsteels that also contained boron had very good HAZ toughness for

the high-heat-input welding processes but had poor toughness at the

3-mm HAZ location for the 75 kJ/inch SA weld. The one titanium-boron steel (Steel 15) that did not exhibit this reduced toughness

was reheated only once for rolling and also contained about twice

as much titanium as the other two titanium-boron steels. Additionally,

the titanium-boron steels had the poorest base-plate toughness of all

the investigated steels so that the boron addition to these titaniumsteels is not an attractive method of producing a steel with improvedHAZ toughness.

References

i. R. W. Vanderbeck, "Investigation of Steels for Improved

weldability in Ship Construction - Phase I," Project SR-1256,

Contract DOT-CG-80588-A, Annual Progress Report - Phase I,

December 19, 1979. SSC-298. AD-AO91106

2. Y. Kasamatsu, et al., "Study of High-Strength Steel for Hiqh

Heat Input Automatic Welding," Tetsu to Hagane, Vol. 61, No. 4,

1975, Lectures 326, 327; Brutcher Translation 9968, 1975.

3. Y. Kasamatsu, et al., "Structural steel Welded With High Heat

Input and Process for its Preparation," German OLS 2,544,858,

Display date April 8, 1976.

4. G. W. Giles, "Automatic Cleanliness Assessment of Steel,"

AISI Publication 112, 1968.

5. N. E. Hannerz, "Weld Metal and HAZ Toughness and Hydrogen

Cracking Susceptibility of HSLA Steels as Influenced by Nb,

Al, V, Ti, and N," Rome Conf on Welding of HSLA Structural

Steels, November 1976, p. 365.

6. N. E. Hannerz and R. M. Jonsson-Holmquist, "Influence of

Vanadium on the Heat-Affected-Zone Properties of Mild

steel," Metal Science, Vol. 8, 1974, p. 228.

37

,L

APPENDIX A Individual Transverse Charpy V-Notch Test Results from theInvestigated Plates

Shear- Shear-Teat Cnerqy Fractuor Lateral Test Cnerqy Fracture Lateral

Temperature, Absorbed, Appearance, Expansion, Temperature, Absorbed, Appearance, Expansion,

Steel _____ ft-lb - mil Steel "F ft-lb % mils

0 107,102,107 70.70,70 80,71,78 12 77 107,96,100 9985,90 81.81,81

-40 81,74.90 50.45,50 66,61,69 0 60.62,72 25.25,30 53,54,62

-60 S9.53.40 25.25,20 55,42,32 -40 46,35,48 20,15,20 45,35,44

-100 10,30.35 510,10 6,21,25 -80 25,10,38 1015.10 21,11,32

-120 18,20,15 SSS 11,13,10 -100 10,5,9 5,5,5 7.3,6

-140 9,6,6 5,5,5 4,2,5 -120 4,9,5 5.55 2.6,2

2 77 $5,60,56 100.1001100 61,66,61 13 77 90,96,95 95,95,95 79,79,82

0 35,35,35 60,65,55 42,38,39 0 43,63,59 25,30.30 43,56,53

-20 25,25,26 35,35,40 30,29,31 -40 50,45,44 25,20,20 46,42,42

-40 21,20,20 25,25,25 27,22,23 -60 27,19,35 15,10,15 25,20,30

-60 19,20,17 15.15.15 20,20,17 -0 10,17,20 5.5.10 12,16,21

-80 12,17,15 10,10,10 12,16,14 -100 7,9,11 5.5.5 6.7,8

3 0 52,57,52 90,90,90 51,55,51 14 40 85,95,94 S5,60,60 '..76.'3

-20 42,51,41 40,55.45 41,49,40 20 78,71,68 50,50,45 62,59,56

-40 40,39,34 40,40,40 38,38,36 0 55,64.55 25.30,25 48,55,49

-80 28,21,23 15,10.15 27,29,24 -40 44,46.43 1S,15,10 39,41,36

-120 17,17,17 SSs 12,11,11 -60 31,23.35 10,10,10 26,21.30

-140 14,16.16 SSs 10,11,12 -80 13,16,10 5.5,5 11,15,9

4 0 96,106,101 60,70.60 75,82,79 15 77 93,107,103 60,60,70 80,84,82

-40 62.83,83 25,35,35 54,67,66 40 81,75,81 40,40,40 71,64.68

-80 65.50,66 15.10,15 52,41,53 0 63,62,69 25,25,30 54,54,58

-120 51.24,36 15,10,10 38,16,28 -40 22,50,20 15,20,15 25,42,21

-140 35.15,9 10,5,5 23,7,5 -60 26,12,12 15,10,10 24,13,12

-160 10,9,10 5,55 5,4,5 -80 8.9.8 SSs 9,10,9

5 0 102,100,107 50.50,55 73,72,73 16 77 121.116,115 70,65,65 85,83,83

-80 52,52,68 20,20,25 42,41,54 40 108,106,115 50,55,60 78,78'-s

-120 45,45,47 15,15,13 34,35,36 0 83,63,63 35,25,25 68,52,53

-190 21,2S,12 10,10,5 19,19,9 -40 21,63,65 10,20,20 22,52,55

-180 23,13,24 SSS 14,8,12 -60 11,15,18 5,10,10 11,12,16

-200 6,6,5 5,5,5 7,5,5 -80 8,8,7 S,5,5 9,9.7

6 0 113,170,215 70,65,70 80,81,77 17 40 106,94,94 50,50,55 75.72,72-40 95,99,83 40,45,40 73,74,64 0 83,65,94 40,30,45 68,55,74

-60 70,37,S8 35,20,25 $9,31,47 -40 50,63.52 20,25,20 44,52.45

-120 37,45,47 15,15,15 30,36.37 -80 19,31,41 10,15,20 17,26,34

-140 7,18,8 5,55 5,13,6 -100 9,16,30 5,5.10 7,13,20

-160 9,9,12 SS,5 6,6,7 -120 5,6,4 SS.S 1.3,1

7 0 113,101,105 60,60,60 76,72,74 18 0 206,234,238 100,1,NU.Dt i 4,ODS.ONU

-20 83,84,67 35,40,40 64,64,67 -20 219,186,236 MO, 70, Ml oMa,90, ma

-40 84,73,71 30,25,25 61,57,54 -40 182,102,127 65,35,40 96,78,90

-80 75,60,57 20,15,15 61,47,46 -60 11,16,234 10.10,DNB 11,151MNU

-120 26,15,19 10,5,5 21,10,13 -80 10,14,14 5.5.5 8,12,12

-140 7,18,s 5,5,5 5,13.6 19 77 81,85,86 50,66,60 71,75.75

0 226,237,221 100,DNV, O0 7?,D,82 40 60,71,66 40,40,40 55,64,71

-40 138,176.190 60,100,100 86,91,89 0 45,60,50 15,20,20 42,52.46

-80 108,112.127 40,45,50 81,91,89 -40 25,35,13 10,15.5 24,26,14

-120 87,91,96 30,30,30 67,70,74 -60 9,14,11 5.10.10 9.14,12

-140 82,12,18 25,5.5 66,9,11 -80 8,5,6 5,5,5 6,4,5

-160 10,6,8 555 9,6,8 20 0 79,63,85 55,50.60 65,57',0

9 0 130,113,119 90,55,60 86.80.82 -20 83,77,68 55,50,45 67,64,58

-60 72,79,74 25,30,25 58.66,61 -40 58,62,60 25,25,25 53,54.53

-120 77,51,45 20,15,15 62,40,33 -60 32,43,30 10,15.10 29,36.27

-140 65,45,30 20,15,10 51.38,26 -100 6.13,19 5,5,S 7,8,10

-160 37,20,17 10,ss 13,9,7 -120 13.6,6 5,5,5 7,1,1

-180 10.15,15 S,5,5 7.11,9 L 0 147,158.185 100,100,100 87,91,96

10 0 05,67,102 50,55.60 72,70,77 -so 120,129,130 60.60,65 83,94,87

-40 87,89,77 35,35,30 69,74,62 -75 117,117,119 50,50,50 73,75,78

-60 39,62,60 10,20,20 33,49,47 -100 87,90,110 30,30,40 68,70,84

-120 35,43,35 10,15,10 28.34,25 -150 15,22,54 5,5.15 11.12.36

-140 35,26,15 10,10.s 25,20,15 -175 13,10.10 5.515 6,2,3

-160 10,7,12 SSS 4,2,6

N 25 120,144,148 60,70,80 81.84.89

11 40 160,230,129 6SD0NSS 90,D06.68 0 116.121,123 50,50.50 81,82,81

20 111,117,127 50,0,50 78,82,84 -25 103,106,107 35.40.40 80,60,77

0 70,130,131 25,40,S0 56,89,96 -so 69,90,91 30.30,30 64,66.68

-40 16,10,35 5,5,10 17,10,19 -100 15,38,40 S.10,10 13.32,33

-60 9,9.11 S,5,S 9,9,10 -125 6,6,12 5,5,5 1.2.9-80 7,9,5 5,5,5 4,6,3

0 77 76,73,75 100,100,100 77,73,74

40 61,82,55 85,90,5 50,61.54

0 36,38,45 35.35,45 40.41.45

-40 25,24,25 20.15.15 28,26,27

-60 15,20,17 5,10.5 14,20.14

D14B means did not break -60 17,11.12 5,5,5 14,9.10

38

... .... .. .. ... ... .... ... :- :,, ';I '' ' ,, ,, , , ,. ... ... P i

APPENDIX B Individual Charpy V-Notch Test Results fr-on FS.4-Wd-Simulation Gleeble Sarrples

She r- Sheer-

Tet Cnergy Fracture i4taral Test Energy Fracture Lsrer.Temeate, Abeobed. pperafnce. txpanon. Tmperaure, Absorbed, Appearance. Expns)on.

Stoe. _ _ tt-lb ____ Steel ______ ftlb

40 37,46,49 15,20,20 29,39,380 12,17,20 3,5,5 11,13,17 12 40 60,49 45,35 46.40-20 16 3 12 20 40.39 25.20 37.34

-40 156,18 ,55 8313 0 1,10,23 15.5,15 16.1,24

2 40 32,30 3 3 13 40 60,56 40,40 48,4720 38.45 25,30 36,390 17,24,23 10,10,10 18,25,22 0 21.5 1,15 24,3,8-20 7,22 5,10 4,19 -40 11.10 5,5 11.8

-40 15,15,17 515.5 13,13,13

27 0,24 30,25 32,27 14 60 30.42 30,35 31.383 407 30,2 00.5 21,40 22,38 20,25 22,3440 13.20,16 10,10.10 20,19,18 20 18,20 20,20 20,210 8,10.10 5,5.5 5,10,10 0 11,12 10,10 13,13

4 77 41,52 20,25 36,43 is 0 20:46,35 20,20,20 21,40,3040 18,22,19 15,15.10 19,20,10 -20 13.14,45 15,15,20 13.1 4,3420 14.15 10,10 13,14 -40 11,13,11 10,10,10 12,13,13

Q 11,10.15 0,5,5 10,11,14 16 40 84,63 40,35 67.5177 24,29 15,15 24,32 0 14,50,40 10,20,20 14,43,3760 20,18 15,10 22,L

40 12,12 10,10 13,13 -40 10,10,15 10,10,10 11.11,150 10,9,10 .5,5 9,12,10 17 0 40,27,36 20,15,20 33,23,31

-20 12,13 10.10 12.146 77 46,14 20,10 36,16 -20 37,8 20,10 31,940 23,34,30 10,15,15 18,25,22 -40 10,22,15 10.10,10 11,18,1420 21.15 10,10 18,120 15,9,8 5,5.5 13,8,6 I8 0 99,95,24 40,40,10 74,73,21

-20 0,10 30,10 63,120 24,41,41 0.15.20 16.30,32 -40 30,9,12 10,5,10 25.10,22

-20 12,23 5.10 9.22 -40 11,10 5,5 1 1.10-40 10,19.21 5.5,5 6,12,14

-60 20.6 5,5 14,2 19 0 60,54,44 35,20,15 53.48,439 71 64,44 15,10 49,36 -40 41,45 15.15 36,37

40 18,18.20 5,5,5 13,13.16 -60 20,20,22 10,10.10 19,23.2020 22,15 S,5 23,16 -to 7,7 5,5 7,60 8.6,8 20 74 40,45,54 25,30,35 34,41,48

9 77 50,62 30,35 43,53 40 10,11 5,5 10,1340 14,17.51 10,15,20 13,18,36 0 6,19,30 5,5,10 6,15,2320 15,16 10,15 15,15 -40 11,10 5,5 12,0 11,8,31 5,5.5 11,9,10 L 100 13,17 10,10 16.16

10 74 25,15 15,15 26,16 74 14,15.14 15,10,10 15,15,14

74 12,31 5,15 13,31 40 9,0 5,5 8,140 24.9,7 10,5,5 24.9.6 0 7,57 5,5,5 5,3,4

a 6,6,6 5,5,5 6,4,6 N 40 94,80 35,30 71,68

11 0 34,18,25 20,10,15 29.17,23 20 74,60,73 25,20,25 62.52.61-20 13,13 55 11,1Z 0 16,62,16 15.25,15 16.51,17-20 11 5,5 6,10 -40 4,10 5.0 7,10-20 9,11, 5,5, 6.1,0-60 0,10,8 5,5,5 7.8,9 U 40 25,30,27 20,20,20 28,30,29

20 12,14,29 10,10.1s 13,15,270 22,4,10 10,5,5 21,7,9

39

N N .4

c .4 N -40 Nni 00 - N NW ~ 0 0 4040

.0 ao. ON tti-iNWN.4ON N WNO ici-iN ~ -- n-is 40N C*i4(i.-iNi -- 0 --- 4 - - - N - . N - -~

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CiNNNiO.-iN40-40C4040Ni0044.4 a--i-. - -- it - 0~~4 -'~1 WiNOF '4~' i "4 '40--a N -o sir' at - 40 i 040 c-in 0 in a.ii -* ui44i.- .4 .,uit iii *-4 -4

U)C)

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0 0 - 0 000 C 0.-i000 441.4 i*400 00.-din NN - ONCO inN - 00 -1000.-ic o~ 0

-' ~ - ~ - - ~ - "c- 0- in .40 N -- 40ui'uia O - 0 in - .00 00 - ~iA ~0 0 - .4 -0 - 000 -0

0 OCin 0.40 NO - 00.-i- NN0 0.40- 0.40 ~inin .4 - - 0.400 0.-lOinddii-40N ,- ~0 - - - 40 u-in - - o -in .~o ii - - - -

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mali 0000 000 000 ~0 00 000 0000 000 coCa Nor noOO 40cc-ia

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6-45 ti-a NW.4 - - - N -0 40 i~ -N - NN -0 - ~0 -N - N-it - -o NNO.4

~0.i NWi4 N -N 004.--i iN.4 40 - N -N - ioi4 0'S - W it - - - 040.4 - ~ii --C 0 -i W N - - N N .4 N .4- 04 - 0 i N N N - 0 40.4 - NON N-i - 40 N N- N N - 40 N - No - N .004 .4 - - - - N -0 N .4 -Nid N -- 0 - - -Nt 4.4 - N NN04.40.-i N -N 0400 -N.4 c-i 40. 4040 4040 40 - - - WO -

r 44 Nt Ni 40.4 -A NN .4iiNtNO 40fl lii .4 .4 N - .4 .4.4

0 0 N 04 - i-i 0

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ho 0-IC .-- 4-0.-~i 0 0.-iLA 00 NOO 000 4.4 NOLA --4 41 - 0i4~ 1.1~. -0 - - - - .4 - - N.40 ~4 - N-i -0

.0 000 .0141 - - - 0 -0 -- 0 - 00- 0 iiAl .40 - 00iiiOi-400 .40 - .4.4 - 0 - 000 NO - 00 -0 N.m NO - "0 .4.400000-- 01 .4-0 N - -. 40 .4 iLA - - .40 00 - - - Nito .4 .4.i 0.-i NO 4 NO 00 .~4

-H N N 40 - N 40.4 04

- NO 04 .40 Si-i 40 N 40 N W.-i 04 - N - 40.-i--I.4 NNN N.404 diNt 00,4 0NN .4.4 NN04 -0 4040 - 0.44040

-H -n NOOX.4 - ~4 N - 40 ---4 iN.4 NN .40 - 40 -N - 40.404 0 40N.4-i- 40.4 01 -N ON--------- 40.4 NO - 04 N N - - .4.4.4 - - - -

~lii .4.404 - 04.4" 4040W 040.~ - .4.440 NO - iNN 40N - 00NN.4 N ~-i -N - N - -N - - -Nt 4.4 - N NN.4.4

.40 N -N ONO -0 0 04 -W 040 040 40 - - 40.4 -

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Cd .4

000 000 fi 00 Ii 00 14cc 00 0000 1400 1400 jiCO 000 001004040 4040 4040 4040 4040.4 t 40 40 N40 4040 4040 4040 tN N N404g II

II II

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2~~~~~ 2m. M m. ~.m~~~'o 'I. m i-m

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In Im Im em m I 1.; 4mm mm

0 ~ ~ ~ ~ ~ ~ I 1% n- r i C m rm~C

4- U.; ;.U mm p.. im ,;me t ., Z

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m~~ w 22 e ~ 2 m

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mm -00 t-m 0 e m 2 2.m o. Z in i

Itm m .m . .z.mm m : C; Ae am : e = = :......... 0. sa m -t :m :. c mm mD

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-- C. ca ca oz TOO ofttSO

APP!iDIX G DPI, Hardness of Butt-Wlded Joints Investigated

Hardness, DPHSAW 75 kJ/in. SAW 180 kJ/in. ESW

HAZ HAZ HAZ HAZ HAZ HAZSteel Base Weld 1 no 3 mm Weld 1 mm 3 mm Weld 1 mm 3 mm

4 145 187 174 166 181 179 166 199 185 164

7 148 193 185 163 192 194 175 209 202 188

11 144 185 211 199 179 184 179 192 178 178

12 147 178 170 160 176 161 160 201 184 163

15 144 196 189 173 184 168 168 196 169 168

17 145 203 185 162 181 164 165 199 177 167

18 146 184 201 175 190 190 165 195 181 164

19 143 186 193 183 192 180 182 191 169 175

L 156 209 206 181 201 203 191 215 205 198

N 146 204 170 163 200 184 160 199 160 151

U 135 213 167 158 189 172 165 192 166 159

44

SHIP RESEARCH COMMITTEEMaritime Transportation Research Board

National Academy of Sciences - National Research Council

The SHIP RESEARCH COMMITTEE has technical cognizance of theinteragency Ship Structure Committee's research program.

Mr. A. D. Haff, Chairman, Consultant, Annapolis, MDProf. A. H.-S. Ang, Civil Engrg. Dept., University of Illinois, Champaign, ILOr. K. A. Blenkarn, Research Director, Offshore Technology, Amoco Production

Company, Tulsa, OKMr. D. Price, Sr. Systems Analyst, National Oceanic and Atmospheric Adnini-

utration, Rockville, MDMr. D. A. Sarno, Manager-Mechanics, ARMCO Inc., Middletown, OHProf. H. E. Sheets, Dir. of Engineering, Analysis 4 Technology, Inc.,

Stonington, CTMr. J. E. Steele, Naval Architect, Quakertown, PAMr. R. W. Rumke, Executive Secretary, Ship Research Committee

The SHIP MATERIALS, FABRICATION, AND INSPECTION ADVISORY GROUPprepared the project prospectus and evaluated the proposals for this project.

Mr. D. A. Sarno, Chairman, hanager-Mechanics, ARMCO Inc., Middletown, OHDr. R. Blclcchl, Manager, Material Sciences, Sun Shipbuilding & Dz Dock Co.,

Chester, PAMr. W. Dukes, Chief Engineer for Structures, Bell Aerospqce Textron,

New Orleans, LADr. C. M. Fortunko, Group Leader, Fracture and Deformation Division,

National Bureau of Standards, Boulder, COOr. E. J. Ripling, President, Materials Research Lab., Inc., Glenwood, IL

The SR-1256 PROJECT ADVISORY COMMITTEE provided the liaison tech-nical guidance, and reviewed the project reports with the investigator.

Dr. H. 1. McHenry, Chairman, Cryogenics Division, National Bureau of Standard4Boulder, CO

Prof. T. W. Eagar, Dept. of Materials Engrg., Massachusetts Inst. of Technology,Cambridge, MA

Dr. M. Korchynsky, Director, AlZoy Dept., Union Carbide Co., Pittsburgh, PADr. J. L. Mihelich, CZimax Molybdenum Co., Ann Arbor, MIDr. C. F. Meitzner, Section Manager, Product Metallurgy, Bethlehem Steel Corp.,

Bethlehem, PAProf. D. L. Olson, Dept. of Metallurgical Engrg., Colorado SchooZ of Mines,

Boulder, CO

I