Ultrasonic surface mechanical attrition treatment (SMAT) was employed to modify the surface microstructural layer of SLM Ti6Al4V ELI biomedical material to improve the fatigue performance. The SMAT method can introduce a nanostructured layer in the SLM sample surface by imposing high-strain-rate plastic deformation. The nanostructured layer improves the mechanical strength of the SMAT-affected zone and induces compressive residual stress parallel with the surface which suppress the initiation of cracks. As a result, the specimen after SMAT exhibits significantly higher fatigue strength than the non-treated sample in both low- and high-cycling regime.

超声表面机械磨损处理（SMAT）被用来修饰SLM Ti6Al4V ELI生物医学材料的表面微结构层，以改善疲劳性能。SMAT方法可以通过施加高应变率塑性变形，在SLM样品表面引入纳米结构层。纳米结构层提高了受SMAT影响的区域的机械强度，并产生了与表面平行的压缩残余应力，从而抑制了裂纹的产生。结果，在低循环和高循环状态下，SMAT之后的样品都比未处理的样品表现出明显更高的疲劳强度。