热轧对铸态LAZ631合金组织及性能的影响  

Effects of Hot Rolling on Microstructure and Mechanical Properties of As-cast LAZ631 Mg-Li Alloy

作　　者：刘旭贺[1,2] 刘豫喜[1] 肖阳[2] 

机构地区：[1]河南工程学院机械工程学院 [2]郑州轻金属研究院金属材料研究所

出　　处：《特种铸造及有色合金》2017年第6期662-665,共4页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51371161)

摘　　要：对铸态Mg-6Li-3Al-1Zn(LAZ631)合金进行了热轧,采用金相观察、X射线衍射分析以及拉伸测试等手段,研究了不同工艺下热轧板的显微组织和拉伸性能。结果表明,LAZ631镁锂合金可进行大变形量的热轧,随着轧制变形量的增加,合金组织得到细化。在较高的轧制温度时,合金中部分Al Li相发生固溶,α相产生(0002)面的择优取向。在大变形量的合金中,β相呈现连续的细线型分布在基体α相中。由于加工硬化和组织细化,合金的抗拉强度随轧制温度升高和变形量的增加而提高,抗拉强度最高达到312.73 MPa。由于温度引发的再结晶程度不同,当轧制温度较高时,伸长率随变形量增加而下降,在较低温度轧制时,伸长率随变形量增加先升高后降低。The as-cast Mg-6Li-3A-IZn （LAZ631） alloy was hot-rolled, and microstructure and tensile properties of the hot rolled plates were investigated by using OM, XRD and uniaxial tensile testing. The results show that the large deformation can be achieved by the hot rolling of LAZ631 alloy. With the increase of rolling deformation, microstructure of the alloy is refined. At a higher rolling temperature, parts of the A1Li phase can be re-dissolved into the matrix and the a phase is generated at the （0002） preferred orientation. The fl phase is distributed in a phase with continuous tiny-line shape under the se- vere deformation. The tensile strength of the alloy is increased with increasing in the rolling temperature and the deformation as a result of the working hardening and microstructure refinement, and the maxi- mum value reaches 312.73 MPa. At a higher temperature, elongation of the hot-rolled alloy is decreased with the increase of the deformation, while at a lower temperature, the elongation is increased firstly and then de- creased with increasing in the deformation rate, which can be attributed to the recrystallization of the alloy.

关 键 词：镁锂合金 热轧 显微组织 力学性能 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TG335.11[金属学及工艺—金属材料]