STS 430의 고온변형 거동에 관한 연구

초록

The dynamic softening behavior of type 430 ferritic stainless steel could be characterized by the hot torsion test in the temperature range of 900 - 1100℃ and the strain rate range of 0.05 - 5/sec. It is found that the continuous dynamic recrystallization (CDRX) was a major dynamic softening mechanism. The effects of process variables, strain (ε), stain rate (), and temperature (T) on CDRX could be individually established from the analysis of flow stress curves and microstructure. The effect of CDRX increased with increasing strain rate and decreasing temperature in continuous deformation. The multipass deformation processes were performed with 10 pass deformations. The CDRX effect occurred in multipass deformation. The grain refinement could be achieved from multipass deformation. The grain refinement increased with increasing strain rate and decreasing temperature. Also, the CDRX in multipass deformation was affected by interpass time and pass strain. The total strain was to be found key parameter to occur CDRX.