Some Needed Precautions When Induction And Flame Hardening

Author:  Almen, J. O.
Source:  Metal Progress, Dec. 1944, p. 1263
Doc ID:  1944003
Year of Publication:  1944
Abstract:  
Surface hardening after carburizing produces parts with residual compressive stresses at the surface--a very desirable condition to enhance fatigue resistance against alternating loads in bending or torsion. Flame hardening produces lower surface compressions, and an underlying layer in tension dangerous to fatigue resistance. Induction hardening acts in a similar way, but the extent of this zone in tension can be limited by controlling frequency and power input.