Evaluation of Different Monitoring Methods of Laser Additive Manufacturing of Stainless Steel

Different monitoring methods for the laser additive manufacturing process were studied in this study. Possibilities and downfalls of three different methods were compared to each other to define their applicability in future on-line and adaptive monitoring use in LAM processes. The material used on all the LAM process tests was EOS StainlessSteel PH1 in fine powder form. In this study, e.g. parameters like scanning speed, layer thickness and hatch space were tested. Based on the results of this study, the pyrometer seems to be more easily adaptable to continuous monitoring than the spectrometer or systems based on active illumination imaging system. It seems that the pyrometer is a promising method for quality control. The ability to control quality through on-line measurements can be further utilized in future e.g. for on-line quality control and dynamic process control, i.e. the ability to change and correct parameters on the fly.