ABSTRACT

Additive manufacturing is progressively paving the way for optimised lightweight components that, due to their typically complex shape, would hardly be feasible with traditional production methods. However, the peculiar mechanical properties of additively manufactured materials limit the accuracy of structural analyses. In this research, a strategy for the implementation of thickness dependent anisotropy into finite element shell models is developed by example of laser sintered polyamide. The material behaviour was modelled by fitting parametric functions to experimental data. Subsequently, a routine was developed to map the adaptive material properties into a finite element model of a complex component. Numeric simulations with standard and mapped properties were compared and validated via experiments. Results show that the proposed approach is superior to the conventional method in predicting the structural response. The method is not only applicable to laser sintered polymers but relevant for all structures, where anisotropy and thickness must be considered.

摘要

增材制造正在逐步为优化的轻质部件铺平道路，这些部件由于通常复杂的形状而无法用传统的生产方法实现。但是，增材制造材料的特殊机械性能限制了结构分析的准确性。在这项研究中，以激光烧结聚酰胺为例，提出了一种将厚度依赖各向异性实现到有限元壳模型中的策略。通过将参数函数拟合到实验数据来对材料行为进行建模。随后，开发了将自适应材料特性映射到复杂组件的有限元模型中的例程。通过实验比较并验证了具有标准特性和映射特性的数值模拟。结果表明，该方法在预测结构响应方面优于常规方法。该方法不仅适用于激光烧结的聚合物，而且适用于必须考虑各向异性和厚度的所有结构。