在本文中,提出了垂直于加载方向具有不同密度的五种梯度功能梯度晶格结构,和表面形态,变形行为,研究了以Ti-6Al-4V为建筑材料,通过选择性激光熔化(SLM)制备的功能梯度晶格结构的压缩性能。结果表明,SLM成型过程的激光能量分布特性使球形金属粉末粘附在晶格结构支柱的表面,导致晶格结构的实际相对密度高于设计的理论相对密度,但最大误差不超过3.33%。在相同的相对密度下,密度梯度垂直于加载方向的所有晶格结构都比均匀晶格结构具有更好的机械性能,特别是,LF的弹性模量,线性的屈服强度,指数的第一个最大压缩强度为28.99%,16.77%,比UNIFORM高14.46%。此外,指数和线性单位体积的能量吸收分别高出38.38%和48.29%,分别,而不是制服。断口形貌分析表明,这些晶格结构的断口形貌表现为凹坑和光滑平面,表明晶格结构在压缩载荷下表现出混合的脆性和延性破坏机制。有限元分析结果表明,当加载方向垂直于密度梯度形成方向时,晶格结构的高密度部分是主要的承载部分,晶格结构两端的密度差越大,弹性模量越大。
In this paper, five grading functional gradient lattice structures with a different density perpendicular to the loading direction were proposed, and the surface morphology, deformation behavior, and compression properties of the functional gradient lattice structures prepared by selective laser melting (SLM) with Ti-6Al-4V as the building material were investigated. The results show that the characteristics of the laser energy distribution of the SLM molding process make the spherical metal powder adhere to the surface of the lattice structure struts, resulting in the actual relative density of the lattice structure being higher than the designed theoretical relative density, but the maximum error does not exceed 3.33%. With the same relative density, all lattice structures with density gradients perpendicular to the loading direction have better mechanical properties than the uniform lattice structure, in particular, the elastic modulus of LF, the yield strength of LINEAR, and the first maximum compression strength of INDEX are 28.99%, 16.77%, and 14.46% higher than that of the UNIFORM. In addition, the energy absorption per unit volume of the INDEX and LINEAR is 38.38% and 48.29% higher, respectively, than that of the UNIFORM. Fracture morphology analysis shows that the fracture morphology of these lattice structures shows dimples and smooth planes, indicating that the lattice structure exhibits a mixed brittle and ductile failure mechanism under compressive loading. Finite element analysis results show that when the loading direction is perpendicular to the density gradient-forming direction, the higher density part of the lattice structure is the main bearing part, and the greater the density difference between the two ends of the lattice structure, the greater the elastic modulus.