挤压态MB350镁合金的高温拉伸变形行为

研究了热挤压态Mg-3Al-3Zn-1Ti-0.6RE镁合金的高温拉伸变形行为和微观组织演变，分析了该合金在温度为623K-723K，应变速率为1x10-4s-1-1x10-2s-1条件下的流变应力随温度和应变速率的变化，归纳了温度、应变速率与流变应力的关系。研究结果表明：温度和应变速率是影响流变应力的主要因素，在变形过程中，流变应力随变形温度的升高和应变速率的降低而减小。在本实验条件下，该合金的变形本构方程可用双曲正弦函数 来描述，应力指数n=3.286，激活能Q=238kJ/mol，表明该合金的高温塑性变形机制主要是位错滑移和攀移。

Tensile deformation behavior of as-extruded MB350 magnesium alloy at elevated temperature

The tensile tests and microstructure evolution of as-extruded Mg-3Al-3Zn-1Ti-0.6RE magnesium alloy at elevated temperature were conducted on WDW3100 microcomputer control electron universal testing machine and Zeiss microscope at strain rates ranging from 10-4 s-1-10-2s-1 and deformation temperature of 623K-723K. The result has shown that temperature and strain rate are the important factors influencing the rheological stress. During the process of deformation, the flow stress decreases with the increase of temperature and the decrease of strain rate. Under this experimental condition, the deformation constitutive equation of the alloy can be described by hyperbolic sine function.Among them, the stress exponent and the activation energy of the as-extrude alloy are 3.286 and 238KJ/mol. The most important deformation mechanism of this alloy is dislocation slip and climb.