Fe-30Mn可降解金属的激光原位合金化及其生物学研究

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

摘要:

3D 打印技术可以制造复杂的结构从而实现骨植入体的个性化定制。采用原位合金化制备非常规配方合金时，可以通过省去制备预合金粉末的步骤，从而降低成本。本研究利用 PBF-LB 原位合金化制备了块状和Gyroid多孔 Fe-30Mn 合金，并探讨了不同打印参数对试样性能的影响。打印过程中激光能量密度较低会导致铁、锰元素混合不均匀，导致材料性能下降；激光能量密度过高则会使锰元素挥发，造成合金成分不符合预期。通过优化激光参数，可获得致密度高、铁锰元素分布均匀的试样，其抗拉强度达到 644.67 MPa，延伸率达到 21.61%，在模拟体液中的腐蚀速率为0.042 mm/年。此外，所得Gyroid多孔支架的孔隙率为 49.84%，0.2% 应变屈服强度为 66.11 MPa，20% 应变压缩强度为 170.76 MPa，弹性模量为 6.41 GPa。间接细胞毒性试验和细胞黏附试验结果表明，该材料具有良好的生物相容性。综上所述，本研究使用PBF-LB 原位合金化制备的 Fe-30Mn 合金有作为可降解人骨植入物的应用前景。

Abstract:

3D printing technology can fabricate complex structures to achieve personalized customization of bone implants. When in-situ alloying is employed to prepare uncommon alloys, the step of preparing pre-alloyed powder can be omitted, thereby reducing costs. In this study, block and porous Fe-30Mn alloys were prepared by PBF-LB in-situ alloying and studied the effects of different printing parameters on the performance of specimens. Insufficient laser energy input during printing leads to inhomogeneous mixing of iron and manganese, which degrades the material’s properties. Excessive 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/year in simulated body fluid. Moreover, the resulting porous scaffold shows 49.84% porosity, a 0.2% offset yield strength 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 showed that the materials had good biocompatibility. Taken together, these results indicate that the Fe–30Mn alloy produced via PBF-LB in-situ alloying holds promise for biodegradable human bone implants.