低成本耐热镁合金AlCeLaSm44的研究开发

Development of Low-cost Heat-resistant AlCeLaSm44 Magnesium Alloy

在耐热AlCeLa44镁合金的基础上开发了低成本的AlCeLaSm44合金。研究了AlCeLaSm44和AlCeLa44合金的显微组织、铸造性能及力学性能。结果表明:两种合金的铸态显微组织均为细小的等轴晶,加入微量Sm元素的合金主要强化相呈短棒状沿晶界分布;两种合金的压铸流动性差异较小,压铸性能相同;AlCeLaSm44合金的力学性能稍高于AlCeLa44合金。这表明,以AlCeLaSm44合金替代AlCeLa44合金是可行的。提出了以低成本人工混合稀土CeLaSm替代Mg-CeLa中间合金制备AE44耐热镁合金的产业化方向。

A low-cost AlCeLa44 Sm44 magnesium alloy was developed on the basis of heat-resistant AlCeLa44 magnesium alloy. The microstructure, casting properties and mechanical properties of the two alloys were investigated.The results were that:(a) As-cast microstructures of the two alloys all were fine equiaxed grains, and main strengthening phases dispersed in the grain boundary in the form of short rod in the alloy containing trace amount of Sm;(b) There was little difference in diecasting fluidity between the two alloys, and their die-casting properties were the same;(c) The AlCeLaSm44 alloy was slightly superior to the AlCeLa44 alloy in mechanical properties. It was seen from these results that replacement of the AlCeLa44 alloy by the AlCeLaSm44 alloy is feasible. Furthermore, a direction of industrialization that heat-resistant AE44 magnesium alloy is fabricated by a low-cost artificially mixed rare earth CeLaSm instead of Mg-CeLa intermediate alloy was put forward.