Microstructure and Texture Evolution Law of Ti-IF Steel for Extra Deep Drawing During Batch Annealing Process

The variation of microstructure of Ti-IF steel of extra deep drawing grade, which having a 83%cold-rolled deformation under simulated batch annealing process at temperature ranging from 480 degrees C to 750 degrees C, was studied by using optical microscopy, X-ray diffraction(XRD) and metallographic micro-hardness tester. The evolution of texture during the recrystallization process was analyzed by Orientation Density Function(ODF). The results show that, the recrystallization temperature of experimental steel is 620-630 degrees C, and the recrystallization process can be accomplished within 1h at660 degrees C. Four major textures after cold rolling are observed as follows, {001}<110>, {111}<110>, {111}<112> and {112}<110>, respectively. At the early stage of recrystallization annealing, texture evolves from {111}to gamma-{111}, which is quite beneficial to achieve high deep drawing performance, the texture {001}<110> and {112}<110> change marginally, as the annealing temperature rises up to 720 degrees C, texture {001}<110> and {112}<110> change into fiber texture gamma-{111}. After annealing, {111}<112> and {111}<110> textures become the two main types.