TGK SPECIAL STEEL PVT. LTD. - HANDBOOK

The Name You Can Trust www.tgkssl.com - 87 - Descriptions and data in the file are typical cases. We will not make guarantee for them. Besides, we reserve the final right to interpret improvement in materials, quality and/or performance. Steel grade (TPMM4) Introduction: The powdered high speed steel with high content of vanadium has advantages of small carbide unevenness, high toughness, high hardness, and good wear resistance. Main application: Cold forging, fine punching, powder pressing, shearing machine, glass fiber- added plastic dies, etc.. Suitable for molds that bear vibration and impact load, such as deep- drawing or punching. Metal cutting blade, cold heading and extruding tool and so on. Chemical Composition: (%) C Cr Mo V W 1.33 4.15 4.60 3.95 5.60 Comparable Steels TIANGONG US Standard ERASTEEL BOHLER TPMMM4 M4 APS2004 S690 Specification Product Round Steel (mm) Wired, Rolled, Forged Steel 5.2-150 Delivery Status: Delivery in annealed condition, annealing hardness 280 HB. Microstructure as Powdered: (1) The carbides are small and uniformly distributed. The size of carbides.5um (the average size of 3 large carbides in 10 fields of view at 1000X). (2) The unevenness of eutectic carbide is not more than level 1. Ultrasonic Flaw Detection Flaw detection standard: according to SEP1921-E/e level of flaw detection and GB/T6402-2008 level 4 of assessment or upon customer-specific requirements. Cleanlineness A B C D Thin Thick Thin Thick Thin Thick Thin Thick 0.5 0.5 1.5 1.0 1.5 1.0 1.5 1.0 SoftAnnealing O O Heating to 860 C~900 C for 3~5h in a protective atmosphere, followed by cooling down to O O 500 C at 10 C/h, and then air-cooling out of the furnace. Stress-ReliefAnnealing O O Heating to 750 C~800 C for 2h, then air-cooling out of the furnace. Microstructure as annealed This third-generation powdered high speed steel is made by hot isostatic pressing of the nitrogen gas atomized powders followed by forging and heat treatment.