technical seminar of tool steel - metapolskt4 qdt skd7 qt41 qdn,qdn1: high-toughness hot work tool...

SANYO SPECIAL STEEL – the Confident Choice

Technical Seminar of Tool Steel

Oct. 11,2012

Sanyo Special Steel Co.,Ltd.

SANYO SPECIAL STEEL – the Confident Choice 2

I. Features of Sanyo’s tool steel

II. Introduction to Hot Work Tool Steels

III. Introduction to Cold Work Tool Steels

IV. Conclusions

Contents


Less chemistry variation

Extremely lowered

non metallic inclusions

The best steel grade

The best

manufacturing process

Excellent stability of steel

characteristics ・Mechanical properties→Stable

・Hear-treatment distortion→Stable

・Premature-cracking accidents

→Substantially reduced

・Increased initial hardness

→Improved die-life

High quality,

High performance,

Meeting all needs

Ready-to-choose steel

groups

Features of Sanyo’s tool steel


Standard ＆ Developed Steels

QH51

(SKH51:M2)

QF5

QDH

QHZ

go

od

Hardness, Wear resistance

QK3M

(SKS93)

QD61

(SKD61:H13)

QKS3

(SKS3:O1)

QCM8

PCM30 (P20 type)

PCM40 (P21 type)

PCM40S (P21 type) Hot Work

Tool Steel

Cold Work

Tool Steel

Plastic Mold Steel

Standard Developed

To

ug

hn

es

s

good

SPMR8

SPM23,30,60 (P/M)

QT41 (SKT4,55NiCrMoV7)

QC11

(SKD11:D2)

QDN,QDN1


Appearance of Damaged Hot Work Die

(Example of heat checking)


Optical Micrograph in Damaged Hot Work Die

①Normal quenched

and tempered structure

②Softened layer

③Plastic flow

④Heat checking

Wear

Large cracking


Wear Deformation Heat checking

Large cracking Heat checking

Hardness (within certain limits)

Toughness (Heat treatment, Steel grade etc.)

Steel grade (higher softening resistance etc./ e.g. SKD61→QDH)

Suitable heat treatment ( Cooling rate of quenching, triple tempering )

Surface treatment (Optimum depth of hard case )

Thermal stress (tool design, production conditions etc.)

Hardness

Toughness

Stress

Preheating of dies

Hardness

Steel grade

Cooling of tools

Stress

Surface treatment

(Nitriding etc.)

The Countermeasures to Improve

The Tool Life of Hot Work Tools

SANYO SPECIAL STEEL – the Confident Choice 8 Toughness

Hig

h-t

em

pera

ture

str

en

gth

Good

Good

QHZ

QDH

SKT4

QDT QDN

SKD7

QT41

Standard & Developed Hot Work Tool Steels

SKH51

QF5

SKD61

QDN1


Hig

h-t

em

pera

ture

str

en

gth

Good

Good

QHZ

QDH

SKT4

QDT

SKD7

QT41

QDN,QDN1: High-toughness Hot Work tool Steel

SKH51

QF5

SKD61

Good hardenability

⇒For Large size

QDN

QDN1


Features of QDN & QDN1

Q:1030oC-30min,A.C.

T: (temp.)-60min,A.C.,2times Q:1030oC-30min,A.C.

T: (temp.)-60min,A.C.,2times

500 550 600 65035

40

45

50

55

60

Ha

rdn

ess / H

RC

Tempering temp. / oC

QD61

QDN

QDN1

550 60040

45

50

55

Ha

rdn

ess / H

RC

Tempering temp. / oC

QDN

QDN1

Quenched and Tempered Hardness


Toughness

0

5

10

15

20

25

30

QDN QDN1

270 X 640 315 X 635

Ch

arp

y im

pa

ct

va

lue

/ J Central portion of material

44-46 HRC , 2mm-V notched

W

H

Range of QD61-ESR

Spec. of NADCA grade E

Range of QD61(H13)

Features of QDN & QDN1


・Heating 600℃→ Cooling with water × 1000 cycles ・Cutting the center of specimens ・Measurement by cross-sectional microstructures

0.00

0.02

0.04

0.06

0.08

0.10

0.12

QDN SKD61A

vera

ge d

epth

of cra

cks （mm

）

Heat-checking Resistance of QDN

Heating(9sec)

600℃ keeping(5sec)

Water cooling(50sec)


Conclusion of QDN & QDN1

①QDN and QDN1 are hot work tool steels modified JIS-SKD61(H13).

②QDN and QDN1 are the steels which largely improved toughness

in particular by the optimization of the chemical compositions.

③QDN1 is the steel modified QDN about high temperature strength.

④Toughness of QDN1 is improved more by applying ESR process.


Hig

h-t

em

pera

ture

str

en

gth

Good

Good

QHZ

SKT4

QDT

SKD7

QT41

QDH: High-strength Hot Work Tool Steel

SKH51

QF5

SKD61

QDH

QDN

QDN1


Tempered Hardness of QDH

400 450 500 550 600 650

35

40

45

50

55

1030℃, Air-cooling

硬さ

(HR

C)

焼戻温度（℃）

SKD61

QDH

Har

dnes

s(H

RC

)

Tempering temperature(℃)


Softening Resistance of QDH

1 10 100 20

30

40

50

硬さ

Test temp.：600℃

Har

dnes

s（Ｈ

ＲＣ

）

Holding time（ｈ）

SKD61

QDH

Initial hardness


① Excellent hardenability and toughness equivalent to SKD61 steel are achieved.

② Higher heat treated hardness is obtainable.

③ Softening resistance is on a par with SKD7(3%Cr-3%Mo) steel.

④ Heat treatment distortion is 50% smaller than SKD61 steel.

Characteristics of QDH

Suitable to applications

･Dies used under abrasive conditions

inducing wear (e.g. Punch dies)


Application examples of QDH

Application Product Grade Die life

Extrusion

die

Aluminum

sash

SKD61 → QDH

(49HRC) (49HRC)

(Nitriding) (Nitriding)

3,000 → 7,800

(Deformation) → (Wear)

Hot press

die Stabilizer

SKD61 → QDH

(53HRC) (55HRC)

(Nitriding) (Nitriding)

6,500 → 13,000

(Deformation)

Hot former Hub unit

3Cr-3Mo → QDH

modified

(50HRC) (51HRC)

8,000 → 12,459

(Wear)


Hig

h-t

em

pera

ture

str

en

gth

Good

Good

QHZ

QDH

SKT4

QDT

SKD7

QT41

QHZ:

Matrix High Speed Steel

SKH51

QF5

SKD61

QDN

QDN1


Charpy Impact Value of QHZ

45 50 55 60 65 70 0

50

100

150

200

250

300

QHZ 1130 ℃，O.Q.

SKD61 1030 ℃，A.C.

SKH51 1180 ℃，O.Q. SKH51

QHZ

SKD61 C

harp

y Im

pact

Val

ue

(J/cm

2 )

Hardness (HRC)

SKD61

QHZ

2mm-C notched


Softening Resistance of QHZ

0.1 1 10 100 30

35

40

45

50

55

QHZ Hardness

(H

RC

)

Holding time (h)

QHZ 1130 ℃，O.Q.

SKD61 1030 ℃，A.C.

SKD61

QHZ

Test temp. : 600℃

Initial hardness


① With high hardness, QHZ has excellent toughness approximately four to six times higher than that of SKH51.

② QHZ has an excellent resistance to softening, better than that of the conventional hot forging grades such as SKD61 and SKD7.

③ Deformation, wear and heat-check are reduced remarkably in comparison with those of SKD61.

Characteristics of QHZ

Suitable to applications

･Dies used under severe conditions (e.g. Hot former dies, Dies for deforming hard workpieces)


Die product Tool steels Die life

Forging

Die

SUS403T

-bolt

SKD7 → QHZ mod (52HRC) (59HRC)

15,000 → 23,000

(Wear)

Forging

Punch

Bearing

race

SKD61 → QHZ

(50HRC) (59HRC)

20,000 → 60,000

(Heat checking)

Forging

press die

CVJ parts M.H.S.S → QHZ

nitriding (58HRC) (58HRC)

5,500 → 17,768

(Cracking) (Heat checking)

Application Examples of QHZ


I. Features of Sanyo’s tool steel

II. Introduction to Hot Work Tool Steels

III. Introduction to Cold Work Tool Steels

IV. Conclusions

Contents


① High Hardness (High-temperature tempering

provides the hardness of

62HRC or higher. )

② Excellent Toughness

and Fatigue Strength

(Extention of die life.)

③ Good Wear Resistence (Equal to or Greater than D2.)

Characteristics of QCM8

Diagram of Cost-Performance


Microstructure of QCM8

QCM8

Smaller primary carbides than SKD11

SKD11

Carbide

Matrix

Improvement of mechanical propaties


Tempered Hardness of QCM8

Fig. Tempering hardness

62HRC or higher

In High-temperature

tempering


Fig. Charpy Impact Value

High Hardness

&

High Toughness

Toughness of QCM8


Excellent

Fatigue strength

↓ Reduce early

Cracking & Chipping

↓

Long die life

Fig. Tension-Compression

Fatigue Strength

Fatigue Strength of QCM8


Application Examples of QCM8

application partspresent

steelcause of life improvemnet of life

shear bladeSCR440

Φ 100CuttingSKD61 wear twice (35,000→70,000 shot)

Die Wheel disk SKD11 chipping 5 times (10,000→50,000 shot)

FB.Punch gear cam shaft SKH51 chipping 3 times (20,000→60,000 shot)

Disk Cutter CVJ Ring SKD11 chipping 6 times (3,000→18,000 shot)

CRF Mandrel Bearing lace SKD11 broken 3.3 times (3,000→10,000 shot)

Forging Bevel gear SKD11 wear&chipping 2.3 times (20,000→45,000 shot)

Punch Bearing lace M.HSS chipping 2.4 times (15,000→36,000 shot)


Following improvement can be obtained

by applying QCM8. ・High hardness (62HRC or higher )

prevent wear and galling. ・Excellent toughness and strength

reduce early cracking and chipping.

QCM8 contributes to large cost reduction

by improvement of die life in severe use environment.

Conclusion of QCM8


1. Sanyo provides suitable steel grades

to required applications with excellent

quality and performance based on Sanyo’s

original technology.

2. Sanyo hopes that our products contributes

to the industries in Argentina.

Conclusions

technical seminar of tool steel - metapolskt4 qdt skd7 qt41 qdn,qdn1: high-toughness hot work tool...

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