Effect of heat treatment on high temperature tensile property and toughness in 9Cr-W-Mo-V-Nb steel

Obara, Satoshi; Yamada, Yoshiyuki*; Nakazawa, Takanori*

This presentation shows the effect of heat treatment on high tensile property and toughness in W added high Cr ferritic heat resistant steel with several heat treatments. In the tensile test at evaluated temperature, the tensile strength was increased with increasing normalizing temperature. On the contrary, the tensile strength was decreased with increasing tempering temperature and time. In the Charpy impact test, fracture appearance transition temperature (FATT) was increased and upper shelf energy (USE) was decreased with increasing normalizing temperature. On the contrary, the FATT was decreased and USE was increased with increasing tempering temperature and time.