In laser powder bed fusion additive manufacturing (AM), the number of build cycles required for a powder to go from its virgin state to a state that can alter final part mechanical properties is currently unknown. While ideal, the use of virgin powder for every AM build is not practical or economical. It is critical to investigate new methods that will help mitigate these cost drivers and enable the use of recycled powder in AM. Presented here is initial work on the use of an inductively coupled plasma (ICP) process to recondition AM powders used in laser and electron beam powder bed fusion, highlighting some challenges faced while developing optimum process parameters. The manuscript focuses on the three-dimensional characterization of used powder, before and after the plasma reconditioning process, in order to quantitatively understand the result of the ICP process on the shape and porosity of the particles. A distinct change in the morphology of the powder was observed before and after the ICP where most, but not all, irregular shaped powder particles and multi-particles were converted into more spherical particles. A detailed analysis of the percentage of spherical and non-spherical particles before and after the ICP process is also included, as well as the process’ effect on particle porosity, which was different for the two powders used, Inconel 718 and Ti-6Al-4V. The results indicate the value of using the ICP process as a viable option for recycling of these two powders.

在激光粉末床熔融增材制造（AM）中，粉末从原始状态转变为可以改变最终零件机械性能的状态所需的构建周期数目前未知。理想的做法是，在每次增材制造中都使用原始粉末是不切实际或不经济的。研究新方法将有助于减轻这些成本驱动因素，并能在增材制造中使用再生粉末，这一点至关重要。本文介绍的是使用感应耦合等离子体（ICP）工艺对激光和电子束粉末床熔合中使用的AM粉末进行预处理的初步工作，突显了在开发最佳工艺参数时面临的一些挑战。该手稿着重于等离子修复过程之前和之后所用粉末的三维表征，为了定量了解ICP工艺对颗粒形状和孔隙率的影响。在ICP之前和之后观察到粉末形态的明显变化，其中大部分但不是全部的不规则形状的粉末颗粒和多颗粒被转化为更多的球形颗粒。还包括对ICP工艺前后球形和非球形颗粒百分比的详细分析，以及该工艺对颗粒孔隙率的影响，这对于所用的两种粉末Inconel 718和Ti-6Al- 4V。结果表明使用ICP工艺作为回收这两种粉末的可行选择的价值。但并非全部，不规则形状的粉末颗粒和多颗粒被转化为更多的球形颗粒。还包括对ICP工艺前后球形和非球形颗粒百分比的详细分析，以及该工艺对颗粒孔隙率的影响，这对于所用的两种粉末Inconel 718和Ti-6Al- 4V。结果表明使用ICP工艺作为回收这两种粉末的可行选择的价值。但并非全部，不规则形状的粉末颗粒和多颗粒被转化为更多的球形颗粒。还包括对ICP工艺前后球形和非球形颗粒百分比的详细分析，以及该工艺对颗粒孔隙率的影响，这对于所用的两种粉末Inconel 718和Ti-6Al- 4V。结果表明使用ICP工艺作为回收这两种粉末的可行选择的价值。