增材制造NiTi合金支架组织性能研究  

A study on the microstructure and properties of additively manufactured NiTi alloy scaffolds

作　　者：张博 高娜 席瑞 王协彬[2] ZHANG Bo;GAO Na;XI Rui;WANG Xiebin(Shandong Institute of Medical Device and Pharmaceutical Packaging Inspection,NMPA Key Laboratory for Quality Evaluation of Medical Materials and Biological Protective Devices,Jinan 250101,Shandong,China;School of Materials Science and Engineering,Shandong University,Jinan 250061,Shandong,China)

机构地区：[1]山东省医疗器械和药品包装检验研究院国家药品监督管理局医用卫生材料及生物防护器械质量评价重点实验室,山东济南250101 [2]山东大学材料科学与工程学院,山东济南250061

出　　处：《山东大学学报（医学版）》2023年第3期63-70,共8页Journal of Shandong University:Health Sciences

基　　金：山东省药品监督管理局课题(SDNMPAFZLX202204);山东省自然科学基金(ZR2020YQ39)。

摘　　要：目的揭示工艺参数以及结构特征对激光粉末床熔融(L-PBF)制备的NiTi合金多孔支架组织性能的影响规律及机制,为制备高性能NiTi合金骨植入体提供基础。方法采用L-PBF工艺制备两组体心立方结构的多孔支架:(1)保持支架杆径200μm不变,改变激光扫描速度500~1000 mm/s,以研究激光扫描速度的影响;(2)保持L-PBF工艺参数不变,改变支架杆径150~500μm,以研究结构特征的影响。采用扫描电子显微镜、差示扫描量热仪、力学试验机等方法研究NiTi合金多孔支架的显微组织、相变行为及力学性能。结果随激光扫描速度增加,支架的实际杆径减小,马氏体相变温度降低,压缩应力下降,循环压缩过程中可回复应变增加;随支架杆径增大,马氏体相变温度升高,循环压缩过程中的可回复应变减小,表现出明显的尺寸效应。结论L-PBF工艺参数及尺寸效应均会影响NiTi合金支架的组织与性能,为了制备符合预期性能的复杂NiTi合金骨植入体,需要根据不同部位的特征尺寸,优化L-PBF工艺参数。Objective To explore the effects of process parameters and feature sizes on the microstructure and properties of NiTi alloy scaffolds fabricated with laser powder bed fusion(L-PBF),so as to provide reference for the fabrication of NiTi alloy orthopaedic implants.Methods The following two groups of NiTi alloy scaffolds with body-centered cubic structure were fabricated:(1)NiTi scaffolds fabricated with different laser scanning speeds of 500-1000 mm/s,while the beam size was fixed at 200μm,to investigate the effects of L-PBF process parameters;(2)NiTi scaffolds with different struct sizes of 150-500μm fabricated with the same L-PBF process parameters,to investigate the size effects.The microstructure,phase transformation behavior and mechanical properties of NiTi scaffolds were examined with scanning electron microscope,differential scanning calorimeter and mechanical testing machine.Results The actual struct size,the martensite transformation temperatures,and the compression strength decreased with the increase of laser scanning speed,while the recoverable strain during cycling compression tests increased with the decrease of scanning speed.The martensite transformation temperatures increased with the increase of the strut size,indicating a clear size effect.Conclusion Both the process parameters and feature size can affect the microstructure and properties of the L-PBF fabricated NiTi scaffolds.Therefore,in order to fabricate NiTi orthopaedic implants with predictable properties,the featured size at different locations has to be considered to optimize the L-PBF process conditions.

关 键 词：增材制造 激光粉末床熔融 NITI合金 骨植入体 尺寸效应 多孔支架 

分 类 号：R687.1[医药卫生—骨科学]