摘要
利用 ５ｋＷ ＣＯ_２激光器对 Ａｌ－５．６ｗｔ％Ｍｎ合金进行表面重熔实验，并对熔池的形貌和微观组织进行了分析研究。实验结果表明；重熔区组织较基体组织大大细化，随着生长速度的增大，重熔区组织由Ａｌ６_Ｍｎ枝晶向α（Ａｌ）＋Ａｌ_６Ｍｎ共晶、α（Ａｌ）胞／枝晶及完全无偏析固溶体转变。熔池中存在的对流和激光扫描过程中工作台运动的不稳定造成了熔池表面波纹状组织和熔池中三维条带状组织的出现。
A series of laser remelted samples of Al-5. 6 wt% Mn alloy have been produced by using a 5kw CO_2 laser. The surface characteristics of these laser - treated samples, their microstructure have also been investigated. Experimental results showed that microstructure changed from Al_6Mn dendrite to α(Al)+Al_6Mn eutectic,α(Al) cellualr/dendrite and segregation -free solid with the increase of growth rate. The major impact of resolidification is refinement of surface microsturcture,which showed in itself various characteristics for the different solidification modes. Two kinds of banded structure caused by convection and unstable moving of the worktable have been observed on the surface of the molten pool and in the melted region.
出处
《应用激光》
CSCD
北大核心
1999年第5期243-246,共4页
Applied Laser
基金
国家自然科学基金资助!59771054
