触变成形对AZ63镁合金组织及性能的影响

Effects of Thixoforming Parameters on Microstructure and Mechanical Properties of Thixoformed AZ63 Magnesium Alloy

研究了触变成形工艺对AZ63镁合金组织及其力学性能的影响。结果表明,在模具温度为200℃,重熔时间为60min时,随着部分重熔温度的升高,初生相晶粒尺寸先减小后增大,抗拉强度和伸长率均先升高后降低;在重熔温度为600℃时,随着部分重熔时间的延长,初生相晶粒尺寸和圆整度均有所增大,抗拉强度和伸长率均有所降低。在模具温度为200℃,重熔时间为60min,重熔温度为600℃时,晶粒尺寸、圆整度、抗拉强度和伸长率达到最佳值,分别为66μm、1.3、247MPa和13.7%。AZ63镁合金在触变成形过程中均表现出很好的工艺可控性,其性能均较常规铸态有很大的提高。

Effects of thixoforming parameters on microstructures and mechanical properties of thixoformed AZ63 Magnesium alloy were investigated. The results indicate that the primary particle size is decreased firstly and then increased, meanwhile, tensile strength and elongation are improved firstly and then decreased with increasing in partial remelting temperature under mould temperature of 200 ℃ and remelting time of 60 min. At remelting temperature of 600 ℃, with increasing in remelting time, size and roundness of primary phase are increased, resulting in the decrease of tensile strength and elongation. Grain size, roundness, tensile strength and elongation of the alloy reach 66 μm.1.3.247 MPa and 13.7%, respectively, at 600 ℃ for 60 min with mould temperature of 200 ℃. AZ63 magnesium alloy exhibits acceptable controllability during thixo-forming, and its properties are superior to those at ascast one.