摘要
依据人体骨骼结构的特点及力学性能要求,基于选区激光熔化工艺使用Ti6Al4V粉末,结合密质骨和松质骨的特点开发低弹性模量的多孔材料。通过与密质骨等密度原则确定的44.92%的孔隙率,并仿制松质骨的多孔结构建立模型,研究了不同能量密度(50 J/mm^(2)、51.8 J/mm^(2))、不同孔径大小(500μm、1 000μm、1 500μm)对多孔材料相关性能的影响。研究表明,基于前述条件制备的体相多孔材料,成形性较好,孔径均匀可控,孔道贯通,外形尺寸可控;试样的孔隙率随孔径的增大而增大,小孔径下500μm的试样更接近设计的孔隙率参数;随着试样孔径的增大,孔径与抗拉强度成正相关关系,但弹性模量逐渐减小;试样实体部分成形质量较好,拉伸测试断口表明基本不存在裂纹等应力缺陷;各试样均不同程度地出现了熔化后的凝固缩孔,为粉末熔化凝固自然特性;多孔结构均能实现低弹性模量的设计要求,51.8 J/mm^(2)能量密度下成形的试样在孔径500μm下的抗拉强度为70 MPa,弹性模量为18 GPa,更接近人体密质骨的性能。
This research focuses on developing a low elastic modulus porous material that aligns with human bone structure and mechanical requirements.The material was developed using Ti6Al4V powder and selective laser melting technology,reflecting the properties of compact and cancellous bones.A model was established by imitating the porous structure of cancellous bone and achieving a porosity rate of 44.92%,following the principle of density similarity to compact bone.The influence of different energy densities(50 J/mm^(2),51.8 J/mm^(2))and pore sizes(500μm,1000μm,1500μm)on the relevant properties of the porous material was studied.The results showed that the bulk porous structure material prepared based on the above conditions had good formability,uniform and controllable pore size,unobstructed pore channels,controllable dimensional accuracy.The porosity rate increased with the increase of pore size,and the pore size of 500μm was closer to the design porosity rate parameter.As the pore size increased,it was positively correlated with the tensile strength,but the elastic modulus gradually decreased.The formed quality of the solid part was good,and the tensile test fracture indicated that there were basically no stress defects such as cracks.There were varying degrees of shrinkage pores after melting in all samples,which was a natural characteristic of powder melting and solidification.The porous structure can achieve the design requirements of low elastic modulus,and the sample formed at an energy density of 51.8 J/mm^(2)reached a tensile strength of 70 MPa and an elastic modulus of 18 GPa at a pore size of 500μm,which was closer to the performance of human compact bone.
作者
唐恩
方杨铭
王坤
刘敬祺
张瑞
Tang En;Fang Yangming;Wang Kun;Liu Jingqi;Zhang Rui(Department of Material Engineering,Zhejiang Industry&Trade Vocational College,Wenzhou 325000,Zhejiang,China)
出处
《应用激光》
CSCD
北大核心
2023年第12期60-68,共9页
Applied Laser
