Mg-Li-Al合金近液相线制浆及部分重熔  

Near-liquidus Slurrying and Partial Remelting of Mg-Li-Al Alloy

作　　者：乐启炽[1] 张新建[1] 崔建忠[1] 路贵民[1] 李红斌[1] 

机构地区：[1]东北大学材料电磁过程研究教育部重点试验室,辽宁沈阳110004

出　　处：《铸造》2003年第4期239-242,共4页Foundry

基　　金：辽宁省科学技术基金(No.20021009);教育部博士点基金(No.21011045003)

摘　　要：采用近液相线铸造方法制备了Mg 5%Li 3%Al合金的半固态浆料。通过对该合金近液相线铸造与常规铸造组织进行比较,以及在不同静置时间、不同冷却速率下对其铸造组织的影响,较详细地分析了近液相线铸造组织的变化过程。试验结果表明,在Mg Li合金熔炼中,添加2%Ca可实现阻燃,但效果不如对一般镁合金;与常规铸造相比,近液相线铸造可获得均匀、细小枝晶的组织结构;适当静置或提高冷却速率有利于组织的细化和均匀化;在适当的部分重熔工艺条件下,坯料组织可获得较理想的触变组织。Semisolid metal ingot of Mg5%Li3%Al alloy was prepared by nearliquidus casting, and its microstructure was compared with that of traditional ascast. The effects of holding time and cooling rate on the microstructure of the alloy were investigated. The results indicate that addition of 2%Ca can be an effective way to prevent MgLi alloy from combustion as smelting, however, which is less valid than in general magnesium alloys. A fine dendritic microstructure could be achieved in nearliquidus casting than in traditional casting, which is composed of a great number of fine, homogeneous nondendritic or rosettizing grains. The advisable holding time or higher cooling rate is favor for refining and uniformity of grains. The thixotropic structure is obtained after partial remelting at suitable conditions.

关 键 词：Mg-Li-A1合金 近液相线铸造 部分重熔 制浆 半固态浆料 

分 类 号：TG292[金属学及工艺—铸造] TG249