Advancing Tungsten LPBF with Pyrometry: Assessing Parameter Stability Using Dimensionless Numbers and Pyrometric Data

To date, researchers have not succeeded in producing defect-free tungsten parts using laser powder bed fusion (LPBF), hindering the commercial realization of LPBF W-parts or reducing it to a few non-load-bearing products. Therefore, research on the LPBF production of components free of defects such as cracks and pores is of great interest to the refractory metals scientific community. The occurrence of such defects can be minimized by the selection of optimized LPBF parameters and by reaction-controlled response to process instabilities. This study presents the use of dimensionless numbers to predict the effect of a particular set of LPBF parameters. In addition, this study demonstrates the effectiveness of in-situ pyrometric signals in predicting the LPBF process and lays the foundation for in-situ parameter modification using pyrometric data. Although this approach is only demonstrated on tungsten, it is reasonable to assume that these principles can be applied to other materials.