Strut-based lattice structures produced by powder bed fusion are prone to characteristic manufacturing defects that alter both their form and surface texture. Most studies in the literature focus on a subset of commonly observed defects, typically radius variation and strut waviness; surface defects remain relatively unexplored. Furthermore, there remains a need for the development of a general finite element modelling framework that can implement a range of defects into any strut-based lattice design. This paper presents a modelling framework for implementing a range of both form and surface defects into finite element meshes of strut-based lattices. A signed distance function forms the foundation for this framework, upon which surface meshes can be modified and converted into tetrahedral meshes via open-source software. The paper demonstrates how radius variation, strut waviness, elliptical cross sections and localised surface defects can be modelled in lattice struts, for which intuitive mathematical definitions are provided. A parametric study is performed to assess the sensitivity of the compressive Young’s modulus of BCCZ and octet-truss lattices to upskin and downskin surface defects. The results showed higher sensitivity in the octet-truss than in BCCZ; both designs were more sensitive to downskin than to upskin defects.

由粉末床融合生产的基于支柱的晶格结构容易出现特征性的制造缺陷，这些缺陷会改变它们的形状和表面纹理。文献中的大多数研究都集中在常见缺陷的子集上，通常是半径变化和支柱波纹；表面缺陷仍然相对未开发。此外，仍然需要开发通用的有限元建模框架，该框架可以将一系列缺陷实施到任何基于支柱的晶格设计中。本文提出了一种建模框架，用于将一系列形状和表面缺陷实施到基于支柱的晶格的有限元网格中。有符号距离函数构成了该框架的基础，在此基础上，可以通过开源软件修改表面网格并将其转换为四面体网格。该论文展示了如何在晶格支柱中对半径变化、支柱波纹度、椭圆横截面和局部表面缺陷进行建模，并为其提供了直观的数学定义。进行参数研究以评估 BCCZ 和八位组桁架晶格的压缩杨氏模量对上皮和下皮表面缺陷的敏感性。结果表明，octet-truss 的灵敏度高于 BCCZ；两种设计都对下层皮肤比上层皮肤缺陷更敏感。进行参数研究以评估 BCCZ 和八位组桁架晶格的压缩杨氏模量对上皮和下皮表面缺陷的敏感性。结果表明，octet-truss 的灵敏度高于 BCCZ；两种设计都对下层皮肤比上层皮肤缺陷更敏感。进行参数研究以评估 BCCZ 和八位组桁架晶格的压缩杨氏模量对上皮和下皮表面缺陷的敏感性。结果表明，octet-truss 的灵敏度高于 BCCZ；两种设计都对下层皮肤比上层皮肤缺陷更敏感。