In-Situ Laser Alloying of Fe-30Mn Biodegradable Metal and Its Biological Research

Abstract:

Block and Gyroid scaffold Fe-30Mn alloys were prepared by powder bed fusion with laser beam (PBF-LB) and in-situ alloying, and the effects of different printing parameters on the performance of specimens were studied. Results show that insufficient laser energy input during printing leads to inhomogeneous mixing of iron and manganese, which degrades the properties of the alloy. Excessively high energy input can cause manganese to vaporize, yielding a composition that deviates from the target. With optimized laser parameters, block specimens exhibiting a uniform Fe/Mn distribution can be obtained with an ultimate tensile strength of 644.67 MPa, an elongation of 21.61%, and a corrosion rate of 0.042 mm/a in simulated body fluid. Moreover, the resulting porous scaffold shows a porosity of 49.84%, a yield strength (0.2% offset) of 66.11 MPa, a compressive strength at 20% strain of 170.76 MPa, and an elastic modulus of 6.41 GPa. The results of indirect toxicity tests and cell adhesion tests show that the alloys have good biocompatibility. In conclusion, the Fe-30Mn alloy prepared by PBF-LB in-situ alloying holds promise for biodegradable human bone implants.