因残余应力导致的翘曲变形是激光选区熔化(SLM)技术亟待解决的关键性技术问题。以两组相同规格的长方体试样为研究对象，基于熔池监测系统采集SLM 成形过程中的熔池数据，对试样翘曲变形和无变形情况下的熔池状态差异进行了对比，从熔池角度分析了翘曲变形的产生机理和具体变形阶段，研究了翘曲变形情况下熔池的变化规律。试验结果表明，试样的翘曲变形产生于成形初始阶段。同时，翘曲变形情况下试样成形层的熔池面积减小，熔池光强增加，通过监测熔池的变化状态可以判断SLM 成形过程中试样是否产生了变形。

Deformation resulting from residual stresses is a key problem in selective laser melting (SLM). The different melting pool conditions between the deformation and normal specimens are compared based on data collected by the melt pool monitoring system. Furthermore, the forming mechanism and deformation process of the specimens is investigated. Results from the experiments suggest that deformation of the specimens occurs in the initial stage of the process. The melt pool area decreases and the intensity of the melt pool increases. The experiments indicate that it is possible to detect deformation of the specimens by monitoring the melt pool behavior.