三维打印316L不锈钢血管支架的电解抛光及力学性能

Three-dimensional printed 316L stainless steel cardiovascular stent’s electrolytic polishing and its mechanical properties

血管支架置入的介入治疗是心血管狭窄和堵塞普遍采用的治疗方法,但支架的传统制造方法如激光切割等工艺复杂且无法制造分叉支架等复杂结构,而三维(3D)打印技术为复杂结构及个性化血管支架制造提供了新的思路。本文采用3D打印技术和0~10μm的316L不锈钢粉末材料打印制作了一种新型血管支架,对打印完成的血管支架进行电解抛光以去除支架表面粘附的粉末,并对抛光后的支架进行了球囊扩张及平面压缩实验。结果表明,本文设计的新型结构血管支架可采用3D打印技术制备;电解抛光去除了粘附的粉末,使支架表面粗糙度Ra由1.36μm降低到了0.82μm;抛光后的支架在球囊压力下外径由2.42 mm扩张到3.63 mm时的轴向缩短率为4.23%,卸载后径向回弹率为2.48%;支架的径向支撑力为8.32 N。3D打印血管支架可通过电解抛光去除表面粉末改善表面质量,并具有良好的扩张表现及径向支撑性能,为3D打印血管支架的实际应用提供了参考依据。

The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage.However,traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents,while three-dimensional(3D)printing technology provides a new method for manufacturing stents with complex structure and personalized designs.In this paper,a cardiovascular stent was designed,and printed using selective laser melting technology and 316L stainless steel powder of 0-10μm size.Electrolytic polishing was performed to improve the surface quality of the printed vascular stent,and the expansion behavior of the polished stent was assessed by balloon inflation.The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology.Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36μm to 0.82μm.The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon,and the radial rebound rate was 2.48%after unloading.The radial force of polished stent was 8.32 N.The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality,and show good dilatation performance and radial support performance,which provides a reference for the practical application of 3D printed vascular stent.