Laser Hatch Distance Can Tune Corrosion Behavior and Mechanical Properties While Maintaining the In Vitro Biocompatibility of Additively Manufactured Mg Alloy WE43

Powder bed fusion laser beam (PBF-LB) of Mg alloys shows strong potential for biodegradable, patient-specific implants. A key challenge is achieving adequate corrosion resistance and mechanical strength while maintaining biocompatibility. This study investigates whether varying hatch distance can balance these properties in PBF-LB processed WE43 (Mg-4Y-3RE-Zr; RE: rare earth elements). Optimal laser parameters were developed for hatch distances of 40, 50, and 60 μm (h40, h50, and h60), and samples were analyzed for microstructure, corrosion resistance, and mechanical properties. Results showed that h60 had a weaker texture and narrower grain size distribution, with fewer grains under 200 μm