AM by scanned laser melting of binder-based metal powder sheets

A recently developed technique to feed metal as feedstock for additive manufacturing is the embedding of metal powder in long sheets through a polymer binder, termed the MAPS technique. The sheet is placed on top of the part during building. One approach is selective melting by a scanning laser beam, generating tracks layer by layer. Different laser beam path strategies have been compared. For a laser beam power of up to 300 W, the process has been studied for AlSi10Mg aluminium powder sheets. Quality issues like inhomogeneous track shapes, oxidation and porosity have been explored and improved. The study of laser remelting and cleaning steps of previous layers has led to smoother, reproducible surfaces and less porosity. Despite remaining challenges, the studies have paved the way for scanning laser beam processing of metal powder sheets, with advantages of efficient, controlled material feeding and flexible melting.