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激光选区熔化（Selective Laser Melting, SLM）技术已经得到广泛关注和快速发展，然而 SLM 成形悬垂结构仍然困难。本文采用 Z 型和岛形两种扫描策略，SLM 成形具有不同悬垂角度的钛合金试件，研究熔池行为与悬垂角度、成形质量之间的关系，阐明了悬垂角度对熔池行为的影响规律以及不同扫描策略下熔池行为对成形表面质量的影响规律。结果表明，熔池在最初几层从最小值快速变大，达到峰值后随着成形高度的增加而缓慢减小；与面扫描相比，轮廓扫描时熔池明显不稳定，振幅大。随着悬垂角度减小，熔池面积变小，悬垂表面粗糙度变大。与 Z 型扫描方式相比，岛式扫描策略熔池面积较小，熔池更为不稳定，引起悬垂表面粗糙度高。
Selective Laser Melting (SLM) technology has gained widespread attention and is rapidly evolving, however, SLM is still difficult to form overhang structures. In this paper, Z-type and island-shaped scanning strategies were used. SLM was used to form titanium alloy specimens with different overhang angles. The relationship between the behavior of the molten pool and the angle of overhang and forming quality was studied. The influence of overhang angle on the behavior of the molten pool As well as the influence of the bath behavior on the forming surface quality under different scanning strategies. The results show that the melting pool rapidly increases from the minimum value in the first few layers, and then decreases slowly with the increase of the forming height. Compared with the surface scanning, the weld pool is obviously unstable and has a large amplitude. As the dangling angle decreases, the pool area becomes smaller and the drape surface roughness becomes larger. Compared with the Z-scan method, the island scanning strategy has a smaller weld pool area and a more unstable weld pool, resulting in a high drape surface roughness.