Qualification of channels produced by laser powder bed fusion: Analysis of cleaning methods, flow rate and melt pool monitoring data

Abstract Laser powder bed fusion, is an additive manufacturing technology that is used in industry for rapid prototyping and manufacturing of aftermarket products, molds and special machine parts. Quality assurance and process stability still require improvement until this technology is ready for large scale serial production. Scan strategies and parameter sets for manufacturing are often fixed when certification processes are finished. Thus, it is important to test the manufacturability of specific design features such as inner channels. In the following we will present the qualification of inner channels in different test parts for the aluminum alloy AlSi10Mg and the stainless steel 1.4542. The testing includes different cleaning methods and air flow rate measurements. Additionally, we will compare such parts and LPBF specific problems to observations with a coaxial melt pool monitoring system.