Temperature Profile and Imaging Analysis of Laser Additive Manufacturing of Stainless Steel

TLDR

Powder‑bed fusion laser additive manufacturing builds metallic parts layer‑by‑layer, has advanced to produce functional aerospace components, yet issues like balling still limit part quality. This study aimed to characterize powder‑bed fusion process behavior by comparing two test setups. The comparison involved measuring temperature profiles and capturing online process photography of EOS PH1 stainless steel parts produced with 200‑W single‑mode fiber lasers. The results indicate that process instabilities arise from variations in energy input during fabrication.

Abstract

Powder bed fusion is a laser additive manufacturing (LAM) technology which is used to manufacture parts layer-wise from powdered metallic materials. The technology has advanced vastly in the recent years and current systems can be used to manufacture functional parts for e.g. aerospace industry. The performance and accuracy of the systems have improved also, but certain difficulties in the powder fusion process are reducing the final quality of the parts. One of these is commonly known as the balling phenomenon. The aim of this study was to define some of the process characteristics in powder bed fusion by performing comparative studies with two different test setups. This was done by comparing measured temperature profiles and on-line photography of the process. The material used during the research was EOS PH1 stainless steel. Both of the test systems were equipped with 200 W single mode fiber lasers. The main result of the research was that some of the process instabilities are resulting from the energy input during the process.