Study of B Microalloying Steel for Base Material of Cold Rolling in CSP Line

摘要

By the technology of B microalloying, Zhujiang Steel developed the base material for cold rolling SPHC, SPHD and SPHE successfully in TSCR line. The microstructure of the steel is coarsened and the strength is decreased. The studies show that B in steel compete N with A1N and reduce the amount of A1N that can refine the grains to coarsen austenite grains; the segregation of B and the coarsening of M_(23)(B,C)_6 on the grain boundary are the reasons of microstructure coarsening. The coarsening mechanisms of B microalloying steel need be studied in depth.