选区激光熔化成形不同孔隙结构Ti-15Mo多孔合金的压缩特性

Compression Properties of Ti-15Mo Porous Alloy with Different Pore Structures Formed by Selective Laser Melting

采用选区激光熔化(SLM)技术分别成形了均匀孔隙体心立方(UBCC)、面心立方(UFCC)及其相应梯度孔隙体心立方(GBCC)、面心立方(GFCC)结构Ti-15Mo多孔合金试样,研究了合金的微观形貌、压缩特性及吸能特性,并分析其压缩失效行为。结果表明:SLM成形4种孔隙结构多孔合金的弹性模量为0.3~1GPa,压缩平台应力为28~48MPa,与人体小梁骨(弹性模量0.2~5GPa和抗压强度4~70MPa)相近;UFCC及GFCC结构合金的弹性模量和抗压强度均高于UBCC及GBCC结构合金的,其中GFCC结构合金最高;梯度孔隙结构合金的吸能特性均优于均匀孔隙结构的,其中GFCC结构合金具有最高的吸能特性,其吸收能量总量为6.60J·cm;均匀孔隙和梯度孔隙结构合金均在结点处发生应力集中而导致开裂。

The porous Ti-15Mo alloy samples with homogeneous pore body-centered cubic(UBCC),facecentered cubic(UFCC)and corresponding gradient pore body-centered cubic(GBCC),face-centered cubic(GFCC)structures were formed by selective laser melting(SLM).The microscopic morphology,compression deformation characteristics and energy absorption characteristics of the alloys were studied.The compression failure behavior was analyzed.The results show that the elastic modulus of SLM formed four kinds of pore structure porous alloys were 0.3-1 GPa and the compressive plateau stress was 28-48 MPa,which were similar to those of human trabecular bone(elastic modulus 0.2-5 GPa and compressive strength 4-70 MPa);the elastic modulus and compressive strength of UFCC and GFCC structure alloys were higher than those of UBCC and GBCC structure alloys,with GFCC structure alloy being the highest.The energy absorption characteristics of the gradient pore structure alloys were better than those of the uniform pore structure,and the GFCC structure alloy had the highest energy absorption characteristics,whose total absorption energy was 6.60J·cm;Both uniform pore and gradient pore structure alloys caused cracking due to stress concentration at the junction.