Warm Deformation Behavior of Steels Containing Carbon of 0. 45% to 1. 26% With Martensite Starting Structure

Warm deformation was investigated for steels containing carbon of 0. 45%, 0. 79%, and 1. 26% respectively with martensite starting structure, using Gleeble 3500 thermomechanical simulator at the temperature ranging from 873 K to 973 K and the strain rate ranging from 0. 1 s−1 to 0. 001 s−1. The effect of carbon content on the deformation activation energy, Z value and the deformation resistance was analyzed. The results showed that the deformation resistance decreased with increasing carbon content. The peak stress of the steel containing carbon of 1. 26% was decreased by 16. 2% compared to the steel containing carbon of 0. 45% under the same condition. This may be attributed to the weakening effect of solid solution strengthening which outweighs the precipitation strengthening of cementite.