It is widely accepted that gas porosity and lack-of-fusion flaws can degrade both static and dynamic mechanical performance of additively manufactured components, limiting the use of AM components in critical applications. However, the mechanisms by which these flaws form are still debated, and their impact on dynamic material performance have yet to be fully quantified. This work outlines the current understanding of the formation mechanisms for gas porosity, lack-of-fusion, and flaws related to melt pool instabilities. Where possible, the spatial and morphological characteristics of these flaws are highlighted, as well as their impact on mechanical properties. The effect of hot isostatic pressing is also discussed.

人们普遍认为，气孔和融合缺陷会降低增材制造组件的静态和动态机械性能，从而限制了AM组件在关键应用中的使用。但是，形成这些缺陷的机制仍在争论中，它们对动态材料性能的影响尚待充分量化。这项工作概述了对气体孔隙，熔合不足以及与熔池不稳定有关的缺陷的形成机理的最新认识。尽可能突出显示这些缺陷的空间和形态特征，以及它们对机械性能的影响。还讨论了热等静压的效果。