Stainless Steel 440, For Construction, Industry, Length : 1000-2000mm, 2000-3000mm, 3000-4000mm, 4000-5000mm

Applications:

• Typical applications include:
• Rolling element bearings
• Valve seats
• High quality knife blades
• Surgical instruments
• Chisels

Heat Treatment:

• Annealing – Full anneal – 850-900°C, slow furnace cool to about 600°C and then air cool. Sub-critical Annealing – 735-785°C and slow furnace cool.
• Hardening – Heat to 1010-1065°C, followed by quenching in warm oil or air. Oil quenching is necessary for heavy sections. Immediately temper at 150-370°C to obtain a wide variety of hardness values and mechanical properties as indicated in the accompanying table.
• Tempering in the range 425-565°C is to be avoided because of reduced impact resistance and corrosion resistance. Tempering in the range 590-675°C results in lower hardness (the product become machinable) and high impact resistance.

Welding:-If welding is necessary pre-heat at 250°C and follow welding with a full anneal. Grade 420 filler will give a high hardness weld (although not as high as the 440C), but 309 or 310 will produce soft welds with higher ductility.