Microstructure, Texture, and Anisotropic Properties of High-Strength Low-Alloy Steel

The effects of cold rolling reduction rates and recrystallization annealing temperature on the microstructure, texture, and anisotropic properties of high-strength low-alloy (HSLA) steel were investigated using scanning electron microscopy and electron backscatter diffraction. The results revealed that the constituents of recrystallized, substructured, and deformed structures were strongly affected by cold rolling reduction rates ranging from 33.3% to 66.7% and recrystallization temperatures ranging from 780 to 840 degrees C. At an annealing temperature of 820 degrees C, when the cold rolling reduction rate was 33.3%, HSLA steel exhibited a low percentage of recrystallization, with cubic, ?-linear, rolled, and Z-texture (the texture at Euler angles ?1 = 30 degrees and F = 20 degrees -30 degrees) structures. The rolled texture and Z-texture increased the strength anisotropy and disappeared at high cold rolling reduction rates. When the annealing temperature was increased from 780 degrees C to 820 degrees C, the proportion of recrystallized grains increased, the rolling texture disappeared, and grain orientation gradually gathered in the cubic texture and ? line texture, resulting in low anisotropy of strength. At an annealing temperature of 840 degrees C, the deformation of the grain disappeared; however, the anisotropy increased compared to annealing at 820 degrees C because of the formation of a new texture of {001}<-1-20>.