Li对GW82K镁合金组织与性能的影响

Effect of Lithium on Microstructures and Mechanical Properties of GW82K Magnesium Alloy

研究了Li对Mg-8Gd-2Y-0.5Zr镁合金(GW82K)的密度、析出相、微观组织及挤压态力学性能的影响。研究结果表明,Li含量高于2.7%时,该合金密度低于所有AZ系工业镁合金的密度。在GW82K镁合金中添加1.5%Li时,合金晶粒粗化并出现Mg_5Gd相,但挤压态合金硬度和抗拉强度提高;当Li添加量达到3%~4%时,出现树枝晶和β-Li相,且Mg_5Gd相随Li含量的增加而增加,挤压态合金硬度和抗拉强度下降,伸长率提高。

The effect of Li on the density, precipitated phase, microstructures and the mechanical property after extrusion of GW82K magnesium alloys were investigated. The results indicate that when Li mass was higher than about 2.7wt.%, the density value of this alloy was less than all of AZ series magnesium alloys density values. When Li contents was equal to 1.5wt.% or so, the coarsen grain and Mg5Gd were found and alloy＇s hardness and tensile strength after extrusion increased. When Li contents increased by 3wt.%-4wt.%, Mg5Gd compound quantities increased and β -Li phase gradually precipitated. At the same time, the elongation after extrusion increased, but hardness and tensile strength decreased.