AISI 4140강재의 재결정 제어변형

초록

The static softening behavior of AISI 4140 could be characterized by the hot torsion test in the temperature ranges of 1000℃∼1200℃ and strain rate ranges of 0.05/sec∼5/sec. Deformation efficiency which was based on dynamic materials model was calculated from flow stress curves obtained continuous deformation. Interrupted deformation was performed with 2 pass deformation in the pass strain ranges of 0.25εp∼3εp and interrupted time ranges of 0.5∼100sec. The dependences of process variables, pass strain (εi), stain rate (), temperature (T) and interpass time (ti), on static recrystallization (SRX) and metadynamic recrystallization (MDRX) could be individually predicted from the modified Avrami's equations. Comparison of the softening kinetics between MDRX and SRX showed that the rate of MDRX was more rapid than that of SRX for the same deformation variables. Controlled multipass deformations were performed using deformation efficiency, static and metadynamic recrystallization of AISI 4140.