TGK SPECIAL STEEL PVT. LTD. - HANDBOOK

The Name You Can Trust www.tgkssl.com - 39 - 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 (TPM638) PRODUCTION DESCRIPTION TPM638 is high wear resistance, high compressive strength under high hardness, and good hardenability. Applications: high performance cutting tools, such as end mills, hobs, planers, etc. SIZE SUPPLIED Product Round (mm) Wire Rolled Forged 3.2-320 Plate (mm) 200 x 503 DELIVERY CONDITION Typical soft annealed hardness is under 300HB. MICROSTRUCTURE 1. The carbides are fine and distribution; the carbide size is 5um (The average of size of 3 grain large carbides under 10 fields of view under 1000X, the maximum value is not greater than 5um). 2. The inhomogeneity of eutectic carbide is not more than grade 1. ULTRASONIC INSPECTION According to SEP1921- E/e standard According to GB/T6402-2008 standard grade 4 According to customer requirements PURITY Type A Type B Type C Type D 1.3 4.10 6.40 5.00 Thin Thick Thick Thin Thin Thick Thin Thick 0 0 1.0 0.5 1.0 0.5 1.0 0.5 PHYSICAL PROPERTIES 3 1. Density (p) : 8.1g/cm 2 2. Modulus of Electricity (E)KN/mm o Temperature/ C 25 400 600 E 240 214 192 o Temperature/ C 25 400 600 30.97 33.10 31.64 3. Thermal Conductivity o Temperature/ C 25 400 600 10.42 11.06 11.36 4. Thermal Expansions o Temperature/ C 25 400 600 420 510 600 o 5. Specific Heat (c) J/KG. C) C SOFT ANNEALING Soft annealing in a protective atmosphere o o at 860 C~900 C for 3~5h, followed by o o slow cooling at 10 C/h down to 500 C , then air cooling. STRESS RELIEF ANNEALING o o Stress-relieving at 750 C ~ 800 C for approximately 2h, then air cooling. CHEMICAL COMPOSITION C Cr W Mo V 1.3 4.2 6.4 5.0 3.1 Co 8.5 Product Round (mm) TPM638 Plate (mm) 1.2-2.4 0.94 x 1.4 -1.68 x 2.0 POWDER METALLURGY