【摘要】 利用等温退火法测定了3种不同Ti含量热轧带钢在冷轧后的退火再结晶温度，通过光学显微镜、透射电镜、显微硬度计和电子万能实验机等研究了Ti含量和退火温度对冷轧钢显微组织和力学性能的影响。结果表明：随着Ti含量的增加，纳米级含Ti析出物对晶界的钉扎作用增强，导致冷轧钢的硬度升高，同时其再结晶开始温度也随之上升，C-Mn钢的再结晶温度为540～560℃,0.05%Ti钢为620～640℃,而0.08%Ti钢则进一步提高至660～680℃;TiC析出物的形成有效抑制了再结晶过程，使得再结晶发生时间延迟，并促使晶粒尺寸细化；随着钢中Ti含量的增加，相同退火温度下冷轧钢的屈服强度呈现上升趋势，而伸长率则有所下降；特别地，当0.08Ti钢在640℃左右进行退火处理时，其伸长率可达到约10%,同时保持较高的屈服强度水平(850 MPa左右)。更多还原

【Abstract】 The annealing recrystallization temperature of three hot-rolled steels with different Ti contents after cold rolling was determined using isothermal annealing method. The effects of Ti content and annealing temperature on microstructure and mechanical properties of the cold-rolled steels were studied by optical microscope, transmission electron microscopy, microhardness tester, and electronic universal testing machine. The results show that with the increase of Ti content, the pinning effect of nanoscale Ti-containing precipitates on grain boundaries is enhanced, resulting in an increase in the hardness of the cold-rolled steel, and their recrystallization starting temperatures also increase. The recrystallization temperature of C-Mn steel is 540 ℃-560 ℃, that of 0.05%Ti steel is 620 ℃-640 ℃, and that of 0.08% Ti steel is further increased to 660 ℃-680 ℃. The formation of TiC precipitates effectively inhibits the recrystallization process, delays the occurrence of recrystallization, and promotes grain size refinement. With the increase of Ti content in the steel, the yield strength of the cold-rolled steel at the same annealing temperature shows an upward trend, while the elongation decreases slightly. Specifically, when the 0.08Ti steel is annealed at about 640 ℃, its elongation can reach about 10% while maintaining a high yield strength level(about 850 MPa).更多还原