Technical Seminar of Tool Steel

Transcription

1 Technical Seminar of Tool Steel Oct. 11,2012 Sanyo Special Steel Co.,Ltd.

2 Contents I. Features of Sanyo s tool steel II. Introduction to Hot Work Tool Steels III. Introduction to Cold Work Tool Steels IV. Conclusions 2

3 Features of Sanyo s tool steel Less chemistry variation Extremely lowered non metallic inclusions 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 The best steel grade The best manufacturing process Ready-to-choose steel groups 3

4 Toughness good Standard & Developed Steels Standard QT41 (SKT4,55NiCrMoV7) Hot Work Tool Steel QD61 (SKD61:H13) Developed QF5 QK3M (SKS93) QDN,QDN1 Cold Work Tool Steel QDH QHZ QKS3 (SKS3:O1) QCM8 QC11 (SKD11:D2) Plastic Mold Steel PCM30 (P20 type) PCM40 (P21 type) PCM40S (P21 type) SPMR8 SPM23,30,60 (P/M) QH51 (SKH51:M2) Hardness, Wear resistance good 4

5 Appearance of Damaged Hot Work Die (Example of heat checking) 5

6 Optical Micrograph in Damaged Hot Work Die 1Normal quenched and tempered structure 2Softened layer 3Plastic flow 4Heat checking Wear Large cracking 6

7 The Countermeasures to Improve The Tool Life of Hot Work Tools Heat checking Wear Deformation Large cracking Hardness Toughness Stress Preheating of dies Heat checking Hardness Steel grade Cooling of tools Stress Surface treatment (Nitriding etc.) 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.) 7

8 High-temperature strength Good Standard & Developed Hot Work Tool Steels SKH51 QHZ SKD7 QDH QF5 SKD61 QDN1 QDN QDT QT41 SKT4 Toughness Good 8

9 High-temperature strength Good QDN,QDN1: High-toughness Hot Work tool Steel SKH51 QHZ SKD7 QDH QF5 SKD61 QDN1 QDN Good hardenability For Large size QDT SKT4 QT41 Toughness Good 9

10 Hardness / HRC Hardness / HRC Features of QDN & QDN1 Quenched and Tempered Hardness QD61 QDN QDN1 50 QDN QDN Q:1030oC-30min,A.C. T: (temp.)-60min,a.c.,2times Q:1030oC-30min,A.C. T: (temp.)-60min,a.c.,2times Tempering temp. / o C Tempering temp. / o C 10

11 Charpy impact value / J H Features of QDN & QDN1 Toughness Range of QD61(H13) Range of QD61-ESR Central portion of material HRC, 2mm-V notched 5 0 QDN QDN1 W 270 X X 635 Spec. of NADCA grade E 11

12 Average depth of cracks (mm) Heat-checking Resistance of QDN 600 keeping(5sec) Water cooling(50sec) Heating(9sec) QDN SKD61 Heating 600 Cooling with water 1000 cycles Cutting the center of specimens Measurement by cross-sectional microstructures 12

13 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. 13

14 High-temperature strength Good QDH: High-strength Hot Work Tool Steel SKH51 QHZ SKD7 QDH QF5 SKD61 QDN1 QDN QDT QT41 SKT4 Toughness Good 14

15 Hardness(HRC) 硬さ Tempered Hardness of QDH SKD61 QDH 1030, Air-cooling Tempering 焼戻温度 temperature( ) ( ) 15

16 Hardness(HRC) Softening Resistance of QDH 50 Test temp.: SKD61 QDH 20 Initial hardness 硬さ Holding time(h) 16

17 Characteristics of QDH 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. Suitable to applications Dies used under abrasive conditions inducing wear (e.g. Punch dies) 17

18 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) 18

19 High-temperature strength Good QHZ: Matrix High Speed Steel SKH51 QHZ SKD7 QDH QF5 SKD61 QDN1 QDN QDT QT41 SKT4 Toughness Good 19

20 Charpy Impact Value of QHZ SKD61 SKD61 2mm-C notched Charpy Impact Value (J/cm 2 ) QHZ QHZ QHZ 1130,O.Q. SKD ,A.C. SKH ,O.Q. SKH Hardness (HRC) 20

21 Softening Resistance of QHZ 55 Test temp. : QHZ QHZ Hardness (HRC) SKD61 35 QHZ 1130,O.Q. SKD ,A.C Initial hardness Holding time (h) 21

22 Characteristics of QHZ 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. Suitable to applications Dies used under severe conditions (e.g. Hot former dies, Dies for deforming hard workpieces) 22

23 Application Examples of QHZ Die product Tool steels Die life Forging Die Forging Punch Forging press die SUS403T -bolt Bearing race CVJ parts SKD7 QHZ mod (52HRC) (59HRC) SKD61 QHZ (50HRC) (59HRC) M.H.S.S QHZ nitriding (58HRC) (58HRC) 15,000 23,000 (Wear) 20,000 60,000 (Heat checking) 5,500 17,768 (Cracking) (Heat checking) 23

24 Contents I. Features of Sanyo s tool steel II. Introduction to Hot Work Tool Steels III. Introduction to Cold Work Tool Steels IV. Conclusions 24

25 Characteristics of QCM8 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.) Diagram of Cost-Performance 25

26 Microstructure of QCM8 Carbide Matrix QCM8 SKD11 Smaller primary carbides than SKD11 Improvement of mechanical propaties 26

27 Tempered Hardness of QCM8 62HRC or higher In High-temperature tempering Fig. Tempering hardness 27

28 Toughness of QCM8 High Hardness & High Toughness Fig. Charpy Impact Value 28

29 Fatigue Strength of QCM8 Excellent Fatigue strength Reduce early Cracking & Chipping Long die life Fig. Tension-Compression Fatigue Strength 29

30 Application Examples of QCM8 application shear blade parts SCR440 Φ 100Cutting present steel cause of life improvemnet of life SKD61 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) 30

31 Conclusion of QCM8 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. 31

32 Conclusions 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. 32