Description This alloy is a High Speed, tungsten type tool steel. It is a deep hardening alloy capable of Rockwell C 64 hardness.
Applications Generally used as cutting tools, broaches and cold extrusion punches, turning, planning and milling cutters for roughing work.
Physical properties (avarage values) at ambient temperature Modulus of elasticity [103x N/mm2]: 217 Density [g/cm3]: 8.70 Thermal conductivity [W/m.K]: 19.0 Electric resistivity [Ohm mm2/m]: 0.65 Specific heat capacity [J/g.K]: 0.46
Soft annealing Heat to 820-850oC, cool slowly in furnace to 550oC then air. This will produce a maximum Brinell hardness of 265.
Stress relieving Stress relieving to remove machining stresses should be carried out by heating to 600-650oC, holding for one hour at heat, followed by air cooling. This operation is performed to reduce distortion during heat treatment.
Hardening Harden from a temperature of 1260-1290oC followed by oil, air quenching or warm bath at 550oC. Hardness after quenching is 63-66 HRC.
Tempering Tempering temperature: 2x 560-580oC. Hardness after tempering is 64-65 HRC.
Forging Hot forming temperature: 1150-900oC. Cold working
In the annealed condition the alloy may be cold worked by conventional methods. Machinability Machinability of T4 is only fair. It ranks as 55% that of the W group water hardening simple tool steels.
Corrosion resistance Although this alloy contains appreciable amount of tungsten it is still not a corrosion resistant alloy. it will rust unless adequately protected.
Welding The alloy may be welded but has a high tungsten content. Consult the alloy supplier for information relative to welding methods.