中文摘要：

在超低温（液氮浸泡）下经多道次轧制制备了纳米孪晶Cu-Zn-Si合金,分析了轧制温度对Cu-Zn-Si合金力学性能和退火行为的影响。结果表明：合金在超低温轧制过程中形成大量厚度约为10 nm的超细孪晶,促进其硬度和强度提高;对超低温轧制的合金退火,更易于诱发再结晶、提高再结晶形核率;利用超低温轧制产生的纳米孪晶界和退火形成的亚微米晶粒,能使合金兼具优异的强度和塑性;经90%超低温轧制和280℃/5 h退火处理后,合金的抗拉强度达787 MPa,延伸率为14.3%。

英文摘要：

The microstructure, mechanical properties and annealing behaviors of Cu-Zn-Si alloy subjected to cryorolling was investigated by transmission electron microscope, tensile tests and microhardness measurement. It is found that cryorolling encourages twinning and dislocation accumulation in Cu-Zn-Si alloy, enhancing the tensile strength and microhardness. Furthermore, cryorolling could provide more nucleation sites for static recrystallization than cold rolling does. After annealing, cryorolled samples own excellent combination of strength and ductility compared with cold rolled ones, due to the nanotwins generated by cryorolling and finer grains. A tensile strength of 787 MPa and an elongation to failure of 14.3% are obtained for Cu-Zn-Si alloy after cryorolling followed by annealing at 280 °C for 5 h.