The research studied the variation of CA-15 stainless steel after annealing, austenitization, quench and tempering. Optimum annealing for best machining condition was found to be 900℃ hold up for 1 hour then furnace cooled to 700 ℃ holding for another 8 hours before air cooling to ambient. Also, 1010 ℃ austenitizated was found to be better than 925 ℃ because of the dissolution of carbides for subsequent quench and tempering treatment. Tempering at 350 ℃ resulted in secondary hardening of the steel austenitized at 1010℃ for 2 or 4 hours. Tempering at 400℃ resulted in temper-embrittlement such that the impact toughness was at the lowest value in this study. However, tempering is between 350-450 ℃ provided the highest tensile strength but the lowest ductile is occurred in 400℃ tempered steel.
CA-15 cast stainless steel Heat treatment Mechanical property Temper ability