Fatigue Property of Ti-6Al-4V Cellular Structures Fabricated by Selective Laser Melting
Selective Laser Melting(SLM)is an Additive Manufacturing(AM)method for fabricating cellular metallic material.SLM Ti-6Al-4V cellular material had been widely investigated due to its biomedical applications.The objective of this study is to investigate fatigue performance and fracture behaviors of SLM Ti-6Al-4V of three different porosity,i.e.45,59,and 68 vol.%cellular structures.The microstructure of SLM Ti-6Al-4V demonstrates α′-martensitic structure due to rapid cooling after SLM.Under cyclic loading,the cellular material fractures in a 45° shear band,the plastic deformation of strut is minimal due to low ductility of α′-martensitic structure.The fatigue strength after 106 cycles decreased from 44 MPa to 8 MPa when the porosity increases from 45 to 68 vol.%.The fatigue strength increases to 18-68 MPa after HIP treatment.HIP can modify the microstructure to a more stable α+β structure and reduce defective pores.HIP thus also increases the normalized fatigue strength ratio to 0.35-0.65 with porosity decreasing from 68 to 45 vol.%.The normalized fatigue strength ratio obtained at lower porosity level is comparable with those of traditionally made Ti-6Al-4V.
Ti-6Al-4V Alloy Cellular structure Computed tomography Fatigue properties Selective laser melting
Dhinakar A. Lin B.H. Chen J.K. Lin H.Y. Chiang P.H. Wu M.W.
National Taipei University of Technology,Institute of Materials Science and Engineering,Taipei 10608 Atomic Craft Corp.,Taoyuan,Chinese Taipei
国际会议
北京
英文
1612-1616
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）