ductile iron society research committee report compiled by ... ductile iron society research report

Download Ductile Iron Society Research Committee Report Compiled by ... Ductile Iron Society Research Report

Post on 11-Jan-2020




0 download

Embed Size (px)


  • Ductile Iron Society RESEARCH PROJECT No. 47

    Literature Summary: Deteriorated Graphite in Casting Surfaces

    Ductile Iron Society Research Committee Report

    Compiled by Doug White - Elkem


    Issued by the Ductile Iron Society for the use  of its Member Companies – Not for General Distribution 


    DUCTILE IRON SOCIETY 15400 Pearl Road, Suite 234  Strongsville, Ohio  44136 

    (440) 665‐3686     

    JANUARY  2012     

  • Ductile Iron Society- Research Committee Report

    literature Summary: Deteriorated Graphite in Casting Surfaces


    DIS Research has shown that a considerable drop in the fatigue life of ductile iron

    castings occurs when there are surface defects or deteriorated graphite in the

    skin of castings. Papers demonstrate this can be due to reactions with the mold or

    cores due to the presence of S from seacoal or binder systems, oxygen such as

    moisture in greensand, or N bearing gases from some sand binder systems.

    Other researchers have studied additional surface quality issues that impact


    Means to minimize or eliminate these issues have been proposed.

    DIS Hot Topic articles and DIS Research reports are available to members on the

    DIS website.

    AFS Transaction papers will be available to people who have previously purchased

    AFS Transactions. Other AFS literature such as Modern Casting articles or copies

    of AFS Transaction papers may be obtained by contacting AFS.

    Doug White: Technical Service Manager, Elkem Materials, Inc. January 2012

  • Literature search -

    Deteriorated Graphite Structures on Cast Iron Skins.

    DIS Literature

    DIS Research Project No. 17 Sulfur in Molding Sand Effect on Flake Graphite at the Cast Surface of

    Ductile Iron Castings George DiSylvestro and Robert Christ

    Ductile Iron Society Research Report No. 44 Effect of Surface Defects on Fatique properties of Ferritic

    Ductile Iron, Rick Gundlack (Stork Climax Research Services) and John McGoldrick (Hodge Foundry, Inc.)

    Ductile Iron Society Research Project No. 45 Graphite Shape Degredation at the Surface of Chemically

    Bonded Sand Molds and Cores.

    DIS Hot Topic #7- 2004 Improving Fatigue Strength (Jim Mullins)

    DIS Hot Topic #3- 2004 Surface Treatments for Ductile Iron (Eugene Muratore)

    DIS Hot Topic #7- 2008 Abnormal Surface Microstructures (AI Alagarsamy)

    Powerpoint Presentation - DIS Meeting June 2011- Lundeen (Foseco)

    AFS Literature

    Boonmee, S., Gyesi, B., Stefanescu, D., "Casting Skin of Compacted Graphite Iron, Part 1: Evaluation and

    Mechanism of Formation," Transactions of the American Foundry Society, Vol. 118, pp. 205-216 (2010)

    Boonmee, S., Stefanescu, D., "Casting Skin of Compacted Graphite Iron, Part II: Influence on Tensile

    Mechanical Properties, ({Transactions of the American Foundry Society, Vol. 118, pp. 217-224 (2010)

    Stefanescu, D.M., Wills, S., Massone, J., Duncan, F., "Quantification of Casting Skin in Ductile and

    Compacted Graphite Irons and Its Effect on Tensile Properties," Transactions of the American Foundry

    Society, Vol. 117, pp. 587-606 (2009)

    Stefanescu, D.M., Juretzko, F.R., "Study ofthe Effect of Some Process Variables on the Surface

    Roughness and the Tensile Properties of Thin Wall Ductile Iron Castings," Transactions of the American

    Foundry Society, Vol. 115, pp. 637-646 (2007)

    Martin, F., Karsay, S. 1., "Localized Flake Graphite Structure as a Result of a Reaction Between Molten

    Ductile Iron and Some Components in the Mold," Transactions of the American Foundrymen's Society,

    Vol. 87, pp. 221-226 (1979)

  • Duncan, F.C., Kraker, J., "A New Test Casting to Evaluate Skin Formation in CGI, "Proceedings of the

    American Foundry Society, 11Sth Metalcasting Congress, paper 10-023 (2011)

    Goodrich, G., "Effect of Cooling Rate on Pearlitic Ductile Iron Mechanical Properties," PowerPoint®

    presentations, copyright ©American Foundry Society (2007)

    La Fay, V.S., Neltner, S.L., "Drifting Away from Seacoal," Modern Casting, Vol. 94, No. 12, pp. 28-30,

    (December 2004)

    Torrance, J., Stefanescu, D., " Investigation of the Effect of Surface Roughness on the Static Mechanical

    Properties of Thin Walled Ductile Iron Castings," Transactions of the American Foundry Society, Vol. 112,

    pp. 757-772 (2004)

    Tinebra, J.P., Wilson, S.J., "Nobake Chemical Binder Systems: Their Effect on Microstructural and

    Physical Properties of Ductile Iron," Transactions of the American Foundrymen's Society, Vol. 101, pp.

    169-173 (1993)

    Xiaogan, H., Jin, X., Wenqing, W., Xuqi, D., Yaoke, W., "Nodular Iron Surface Deterioration Due to PTSA in

    Resin," Transactions of the American Foundrymen's Society, Vol. 100, pp. 9-15 (1992)

    Kambayashi, H; Une, H; Kurokawa, Y; Ito, T; Mikamoto, S; Miyake, H., "Mold Surface Analysis Evaluation

    of Inclusion Defects Occurring in Cast Iron Produced in Green Sand Molds," Transactions of the

    American Foundry Society, Vol. 112, pp. 787-799 (2004)

    Lawerenz, M., "Shot Peening Ductile Iron," Modern Casting, Vol. 80, No.2, pp. 51-53 (Feb 1990)

    Watmough, T., Malatesta, M.J., "Strengthening of Ductile Iron for Crankshaft Applications," Transactions of the American Foundrymen's Society, Vol. 92, pp. 83-99 (1984)

    Shrikhande, V., "Sulfur Control at the Mold/Metal Interface of Cast Ductile Iron," Modern Casting, Vol. 85, No. 1, p. 44 (Jan 1995)

    Mampaey, F., Li, P.l. , Wettinck, E., "Variations in Strength along the Casting Diameter", "Transactions of the American Foundrymen's Society" 2003, AFS Library Copy 20030283A.pdf

    Other literature

    Influence of Surface Quality on Fatigue Behavior of Nodular Cast iron, M.Kokavec and R. Konecna

    University of Zilina, Slovakia and G. Nicoletta University of Parma, Italy. Acta Metallurgica Slovaca,

    volume 17, 2011, No.2, pp 99-105

    The Mechanism of Formation of Casting Skin in CGI and its Effect on Tensile Properties, Boon me and

    Stefa nescu www .scientific.net/KE M .457.11

  • Factors Influencing the Surface Graphite Degeneration in Ductil.e Iron Castings in Resin Mold Technology.

    R.iposan, Chisamera, Stan, Skaland TSINGHUA Science and Technology ISSN 1007-0214 08/20 pp157-

    163 Volume 13 Number 2 April 2008

    Flake Graphite Layers at the cast Surfaces of Nodular Iron Castings. BCIRA Broadsheet 234

    Private communication



    Ductile Iron Society · ProjectP17

    A Research Project of the Committee on Structmal Control


    Project Direction - George Di Sylvestro Project Assistance- Amertcan Colloid Company

    Project Summary - Robert J . Christ


    This project investigated the role of sulfur in molding sand on the formation of a layer of flake graphite just below the ~-urface of ductile iron castings. Information was compiled by questionnaire from 28 member foundries on the prevalence of this condition and procedures used to control sulfur in system molding sands. Six volunteers participated in round robin resting to determine reproducibility of sulfur analyses methods. Eleven foundries then provided statistical data on system sand sulfur analyses from their own facilities using recommended practices identified in this study. A literature survey identified information on effec1s of sulfur and threshold levels.

    • The prevalence of flake graphite and the adverse effects wns confmned by ~ ·of producers, but . few foundries routinely monitor sulfur in sand. Those tbat do. generally use Leco type equipment. although no standaids exist with regard to instrument models or procedures.

    • Unless the f1ako graphite is comple1dy removed by machining, the surface hardness and bending fatigue properties of the casting will be reduced.

    • It is recommended that sulfur in system sand be controlled to

  • DIS Research Project No. 44




    The fatigue strength offerritic ductile iron, Grade EN-GJS-400-18U-LT. was determined for large section castings measuring 4 by 24 by 24 inches. Fatigue testing was conducted in bending fatigue in order to determine the influence of surface conditions on fatigue strength. Test specimens with various surface conditions were evaluated, including notched and un-notched specimens, as well as those containing surface defects typical of heavy section ductile iron castings. In addition, smaller, round axial fatigue test specimens were tested to produce the more typical laboratory fatigue test properties for comparison with other materialS tested for the Ductile Iron Society.

    Bending fatigue testing was conducted on two groups of specimens. A large number of specimens of intermediate size and obtained from the drag surface were tested to evaluate the effects of surface condition and notch sensitivity. Those specimens were nominally 1.6 in. thick by 2.0 in. wide by 12 inches long. Various notches were machined into the surface of the bars including U notches and V notches.

    The se


View more >