TGK SPECIAL STEEL PVT. LTD. - HANDBOOK

The Name You Can Trust www.tgkssl.com - 37 - 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 (TPM558) PRODUCTION DESCRIPTION TPM558 is high alloy steel, high wear resistance, high, red hardness. Applications: Heavy machining tools (not only for the processing of steel, but also for the processing of non-ferrous metal such as nickel base and titanium); hobs, slotting cutter, milling knives, complicated cutter, threaded cutter, etc. SIZE SUPPLIED Product Round (mm) Rolled Forged 22.320 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 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 254 218 196 o Temperature/ C 25 400 600 20.96 23.80 23.01 3. Thermal Conductivity o Temperature/ C 25 400 600 10.32 10.99 11.49 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 1.6 4.8 10.4 2.0 5.0 Co 8.0 POWDER METALLURGY