A novel method for determining printability of aluminum alloys for LPBF applications.

Laser powder bed fusion (LPBF) additive manufacturing has many benefits when compared to traditional manufacturing processes. The rapid solidification seen in the melt pool limits the alloys that can be used in LPBF printing due to issues with segregation and cracking especially in aluminum alloys. This makes research and development of alloys that print well of paramount importance. While tools like CALPHAD and crack susceptibility models can help to guide alloy development, the model results must be verified experimentally. Traditionally, powder of the alloy of research interest is produced to test printability. This method can be cost prohibitive. This work sets out to show that lasering melt pools into mini-arc melted samples, referred to as single line scans, of the aluminum alloy of interest is an effective method to determine the alloys printability and a window of process conditions, without having to fabricate a custom powder. Transverse sections on the line scans are examined for cracks in the melt pool regions, and segregation of alloying elements. High strength aluminum alloys of interest are identified using the CALPHAD method and crack susceptibility models. Work funded through Army contract W911NF20020190.