(1. 重庆大学 国家镁合金材料工程技术研究中心，重庆 400044；
2. 重庆大学 材料科学与工程学院，重庆 400044；
3. 重庆大学 机械传动国家重点实验室，重庆 400044)
摘 要: 研究“轧制+固溶+轧制”工艺和“固溶+轧制”工艺对Mg-Gd-Y-Zn-Mn合金中LPSO相及其组织性能的影响。结果表明：经“轧制+固溶+轧制”工艺处理后，合金中块状LPSO相较小，且分布弥散，合金的组织由细小的再结晶晶粒组成，最终合金获得较好的综合力学性能，抗拉强度(UTS)达到347 MPa，伸长率(EL)为11.6%；经“固溶+轧制”工艺处理后，合金中块状LPSO相较粗大，分布不均匀，由于固溶退火后析出的层状LPSO相阻碍合金的再结晶，轧制后合金中仍存在变形组织，最终合金具有相对较高的抗拉强度(UTS为358 MPa)，但是伸长率较低(EL为6.6%); 对比而言，“轧制+固溶+轧制”工艺易进行更大压下量轧制，进而获得更高综合力学性能。
关键字: Mg-Gd-Y-Zn-Mn合金；轧制工艺；LPSO相；显微组织；力学性能
（1. National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China？
2. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China？
3. The State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, China）
Abstract:The influences of “rolling + solution treatment + rolling” process and “solution treatment + rolling” process on LPSO phase, microstructure and property of Mg-Gd-Y-Zn-Mn alloy were investigated in this work. The results show that the block-shaped LPSO phases in the alloy are smaller and dispersive after processing with “rolling + solution treatment + rolling”. And the microstructure of the alloy consists of tiny recrystallization grains. And then the alloy finally obtains a good comprehensive mechanical property, UTS=347 MPa, EL=11.6%. On the other hand, the block-shaped LPSO phases in the alloy are coarser, and its distribution is heterogeneous, after processing with “solution treatment + rolling”. And the deformed structure still exists in the alloy after rolling, since the recrystallization is hindered by the layered LPSO phases which precipitated after solution treatment. Then the alloy finally exhibits a high tensile strength of 358 MPa, but a bad plasticity of 6.6%. The increase of the rolling reduction is beneficial to improve the mechanical property of the alloy. By contrast, the rolling with greater reduction can be processed easily with “rolling + solution treatment + rolling” and then the higher mechanical property can be achieved.
Key words: Mg-Gd-Y-Zn-Mn alloy; rolling process; LPSO phase; microstructure; mechanical property
