模压形变处理后Q235钢的热稳定性

摘要

The 2-pass and 10-pass constrained groove pressing deformation were conducted on Q235 steel, respectively, and then the steel was annealed at different temperatures;the thermal stability of the groove pressed steel was studied.The results show that after annealing under 500 ℃, the microstructures of 2-pass and 10-pass groove pressed specimens were in the recovery stage.The grains were still uniform and fine equiaxed grains, similar to those before annealing.After annealing at 500-680 ℃, the recrystallization occurred in the specimens and the grains grew with the increase of annealing temperature.After annealing at 680 ℃, the microstructure of 10-pass groove pressed specimen was more uniform than that of 2-pass groove pressed specimen.With the increase of annealing temperature, the hardness of the 2-pass and 10-pass groove pressed specimens both decreased and the hardness decrease rate of 10-pass groove pressed specimen was relatively large after annealing at 250-600 ℃.However, the hardness was slightly higher than that of 2-pass groove pressed specimen after annealing at 680 ℃.%对Q235钢分别进行了2道次和10道次模压形变处理,再在不同温度下进行了退火处理,研究了模压形变处理后该钢的热稳定性能.结果表明:在低于500 ℃退火时,模压2道次和10道次试样的组织均处于回复阶段,晶粒与退火前的相似,仍为均匀细小的等轴晶粒;在500~680 ℃退火后,试样发生了再结晶且晶粒随退火温度的升高而长大;在680 ℃退火后,模压10道次试样的组织比模压2道次试样的均匀;随着退火温度的升高,模压2道次和10道次试样的硬度均下降,且模压10道次试样在250~600 ℃退火后其硬度的下降速率更快,而在680 ℃退火后的硬度又稍高于模压2道次试样的.