Heat-treatable steels are in the mechanical construction steel range. They are characterized by carbon content usually in excess of 0.25%, and may or may not be alloys.
Heat-treatable steels are used to fabricate parts that require a combination of strength and tenacity, with relatively uniform values throughout the cross section or down to a certain depth. These properties are attained by means of quenching and tempering, which comprise the heat-treatment process.
Responds well to heat treatment, particularly for larges cross sections. Offers a good combination of strength, ductility and tenacity.
Truck, tractor and car camshafts, gears, arms and wheelends, and large cross-section tempered parts in general.
COPANT 4340; SAE 4340; AISI 4340; UNS G43400; DIN 40CrNiMo6 (1.6565); JIS SNCM 6;
Chemical Composition (% BY WEIGHT)
0,38 – 0,43
0,60 – 0,80
0,15 – 0,35
1,65 – 2,00
0,70 – 0,90
0,20 – 0,30
THERMAL TREATMENT AND PROCESSING TEMPERATURES (°C)