非对称挤压腔循环膨胀挤出法制备AZ31合金的显微组织和力学性能

• 作 者: 梁敏洁 郑杰 刘欢 姚宝星
• 机 构: 中北大学 材料科学与工程学院,太原 030051
• 出 处: 中国有色金属学报（英文版）
• 发表日期: 2022年1期
• 关键词: magnesium alloy microstructure cyclic expansion extrusion mechanical properties

研究AZ31合金在非对称挤压腔循环膨胀挤出(CEE-AEC)过程中的显微组织、织构演化和力学性能.结果表明,在CEE-AEC过程中发生连续动态再结晶(CDRX)和不连续动态再结晶(DDRX).经过3道次变形后,变形试样的显微组织得到细化,非对称型腔区域合金的平均晶粒尺寸为6.9μm.随着道次的增加,基体织构的最大强度增大,并且变形过程中基体织构发生偏转.非对称型腔区域合金的基底织构从法向(ND)到挤压方向(ED)倾斜约±45°.晶粒细化强化和织构偏转显著提高变形合金的综合力学性能.3道次后,非对称型腔区域合金的拉伸屈服强度、极限抗拉强度和断裂伸长率分别为146 MPa、230 MPa和29.7％.“,”The microstructure, texture evolution and mechanical properties of AZ31 magnesium alloy were investigated during the cyclic expansion extrusion with the asymmetrical extrusion cavity (CEE-AEC) process. The results show that continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX) occur during the CEE-AEC process. After 3 passes, the microstructures of the deformed samples are refined, and the average grain size of the alloys in asymmetrical cavity region is 6.9 μm. The maximum intensities of the basal textures increase with the increase in the number of passes, and the basal textures are deflected during the deformation process. The basal texture of the alloys in asymmetrical cavity region is tilted by approximately ±45° from the normal direction (ND) to the extrusion direction (ED). Grain refinement strengthening and texture deflection significantly improve the comprehensive mechanical properties of the deformed alloys. After 3 passes, tensile yield strength (TYS), ultimate tensile strength (UTS) and elongation- to-failure of the alloy in the asymmetric cavity region are 146 MPa, 230 MPa and 29.7％, respectively.