Structural characterisation and mechanical behaviour of porous Ti-7.5Mo alloy fabricated by selective laser sintering for biomedical applications

摘要

Ti foams are attracting increasing interest in skeletal repair and dental implant at present. In this study, porous Ti-7.5Mo alloy was prepared from mixed powders of metal and binder by selective laser sintering, and mainly the characterisations on porous, microstructural and mechanical features were performed. The results show that the pore morphology varies from opened to closed pores as the alloy is sintered from1000 to1200 degrees C, and the porosity level and pore size reduce in 60-26% and 135-54 mu m ranges, respectively. A laminar microstructure composed of major a and minor beta phases is observed in the porous alloy together with slight a precipitations. Compressive stress-strain curves exhibit a three-stage deformation behaviour including elastic, yield and fracture regions. Elastic modulus and yield strength increase with decreased porosity in 3.26-12.7 GPa and 58.6-182.5 MPa ranges, respectively. The relationship between the relative mechanical properties and relative density obeys a power law relation. The mechanical properties could be adjusted by porosity to meet the basic requirement of natural bones.