Hot Processing Maps and Texture Evolution during Hot Compression of CF170 Maraging Stainless Steel

Abstract

In this work, the hot processing maps of CF170 maraging stainless steel were generated by using flow stress data obtained from an isothermal compression experiment on the Gleeble-3800 hot compression simulator. The microstructure corresponding to the stable regions in the hot processing map was observed with an optical microscope. The results showed that the steel is susceptible to deformation temperature, strain, and strain rate, and the optimal hot working parameter is a strain rate range of 0.01∼0.1 s−1 and a temperature range of 1350∼1373 K when the strain is 0.6. In addition, the texture evolution of prior austenite during hot compression was investigated based on reconstructing a parent grain by Electron Back-Scattered Diffraction. The results showed that twinning-induced dynamic recrystallization is another mechanism except for strain-induced dynamic recrystallization at a higher strain rate. Further, the deformed microstructure with a Cube texture (1 0 0) 〈0 1 0〉 will preferentially nucleate, and the increase in temperature makes the Cube texture (1 0 0) 〈0 1 0〉 change to the rotated Cube texture (1 0 0) 〈1 1 0〉, and the increase of strain rate inhibits the growth of recrystallized grains and weakens texture.