TGK SPECIAL STEEL PVT. LTD. - HANDBOOK

The Name You Can Trust www.tgkssl.com - 27 - 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 (M7) Smelting method: 15T intermediate frequency furnace +LF+VD+ESR Main characteristics: M4 is high-speed tool steel of tungsten and molybdenum system. It’s featuring with favorable hardness, abrasion resistance, favorable softening resistance under high temperature and tenacity. Major applications:  Turning, chipping and slotting tools, spiral drills, thread drilling, contour cutting tools, broaching tools, reamers. Chemical constituent %: C Si Mn W Cr Mo V Co P S 0.98 0.35 0.3 1.80 4.00 8.50 1.90 - ≤0.028 ≤0.010 Physical property: Room temperature density (Kg/m 3 ) Specific heat of room temperature (J/Kg·K) 20ºC thermal conductivity (W/m•K) Elastic modulus (N/mm 2 ) Linear expansivity (×10 -6 K) 20~200ºC 20~400ºC 8.30 0.46 19.0 217,000 12.5 13.2 Ultrasonic flaw detection: As per SEP1921 D/d or customer requirements. Purity: Class A Class B Class C Class D Fine Coarse Fine Coarse Fine Coarse Fine Coarse 0.5 0.5 0.5 0.5 0.5 0.5 1.0 0.5 Delivery state: (1) Delivery under balling annealing state, delivery hardness ≤269HB. Supply specification: Product name Specification Round bar Ø15~80mm HIGH SPEED STEEL