The Effect of Anisotropy on the Optimization of Additively Manufactured Lattice Structures
The Effect of Anisotropy on the Optimization of Additively Manufactured Lattice Structures
复制标题
各向异性对增材制造晶格结构优化的影响
DOI：
10.1016/j.addma.2017.07.004
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发表时间：
2017
影响因子：
11
通讯作者：
K. Shea
中科院分区：
文献类型：
--
作者：
T. Stanković;Jochen Mueller;K. Shea
构建方向是对增材制造部件中的材料性能最有影响的因素之一。高级应用，例如针对轻质优化的晶格结构，通常依赖于较小的安全裕度，因此受到的影响特别大，但研究尚未远远超出纯粹的经验表征。本文的重点是详细研究各向异性的影响，通过制造的机械性能和构建方向的整个结构时，受到优化。首先，制定了压缩和拉伸状态的材料属性模型。然后，广义最优性准则方法扩展到固定拓扑网格结构的位移，应力和欧拉屈曲的约束。后两者被公式化为与满应力设计递归组合处理的局部约束。结果显示，当使用单向测试的属性时，可能会导致过早失效的重要安全螺纹，到目前为止，情况就是如此，而不是本文开发的完整各向异性模型。如果反向使用，该算法会产生构建平台上结构的最佳方向，从而在保持机械性能的同时进一步减轻重量。
The build orientation is one the most influential factors on material properties in additively manufactured parts. Advanced applications, such as lattice structures optimized for lightweight, often rely on small safety margins and are, hence, particularly affected, but research has not gone far beyond the pure empirical characterization. The focus of this paper is to investigate in detail the influence of anisotropy induced through fabrication on the mechanical performance and build orientation of whole structures when subject to optimization. First, a material property model for both compression and tension states is formulated. Then, the Generalized Optimality Criteria method is extended for fixed topology lattice structures with respect to constraints in displacement, stress, and Euler buckling. The two latter are formulated as local constraints that are handled in combination with Fully-Stressed Design recursion. The results reveal significant safety threads likely leading to premature failure when using properties from one-directional tests, as is so far the case, rather than the full anisotropy model developed herein. If used inversely, the algorithm yields the optimal orientation of a structure on the build platform, allowing further weight reduction while maintaining the mechanical properties.