采用Z-型和岛式两种扫描策略，利用激光选区熔化（SLM）技术成形了具有不同悬垂角度的Ti6Al4V试件，研究了熔池行为与悬垂角度和成形质量之间的关系。结果表明，成形过程中，熔池面积先快速变大，达到峰值后，再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，熔池面积振幅大。随着悬垂角度的减小，熔池面积变小，悬垂表面粗糙度变大。与Z-型扫描方式相比，岛式扫描策略下熔池面积较小，熔池更为不稳定，且悬垂表面粗糙度高。

With the Z-scan and Island-scan two schemes and selective laser melting (SLM) technology, Ti6Al4V specimens with different overhang angles are fabricated, and the relationships among molten pool behavior, overhang angle and forming quality are studied. The results show that, in the forming process, the molten pool area first increases sharply till arrives at a peak value, and then decreases slowly with the increment of fabrication height. Compared with that for the plane-scan scheme, the molten pool for the contour-scan scheme is more obviously instable and its area has a larger amplitude. With the decrement of overhang angle, the molten pool area becomes small and the overhang surface becomes rough. Compared with that for the Z-scan scheme, the molten pool area for the Island-scan scheme is smaller, the molten pool is more instable, and the overhang surface roughness is higher.