对铸态Mg-9Gd镁合金挤压变形后再进行不同的热处理, 研究了不同处理后Mg-9Gd镁合金的组织与力学性能。结果表明: 挤压态Mg-9Gd合金的显微组织由大量的细小等轴晶粒和少量中间相组成, 中间相破碎成大量细小的块状颗粒, 沿平行于应力方向呈带状分布; 相比铸态合金, 挤压态合金的σb提高了89.8%, σ0.2提高了44.1%, δ达到了19.5%; 挤压态合金经520 ℃×2 h+200 ℃×8 h处理后, 强度和塑性降低, σb, σ0.2分别为231.4, 129.3 MPa, δ为15.2%; 经200 ℃×14 h处理后, 挤压态合金的强度明显提高, σb, σ0.2分别达到254.2, 180.3 MPa, 但塑性进一步降低, δ为10.5%。

The as-cast Mg-9Gd alloy was extruded, and then was hot treated, the microstructure and mechanical properties of the Mg-9Gd alloy after different treatments were studied. The results show that the extruded alloy contained amounts of refine equiaxed grains and a small number of intermediate phases, and the later was broken to massive block particles along the stress direction distribution in belt. Comparing with the as-cast alloy, the tensile strength (σb) and the yield strength (σ0.2) of the extruded alloy increased by 89.8% and 44.1% , and the elongation reached to 19.5%. The σb and the σ0.2 decreased after the extruded alloy was treated by 520 ℃×2 h+200 ℃×8 h, and the σb, σ0.2 were 231.4, 129.3 MPa, and δ was 15.2%. The aging treatment of 200 ℃×14 h obviously enhanced the strength, σb and σ0.2 up to 254.2 MPa and 180.3 MPa, but the plasticity decreased further, and δ was 10.5%.