Stoia Dan Ioan, Marsavina Liviu, Linul Emanoil
Department of Mechanics and Strength of Materials, Politehnica University of Timisoara, 1 Mihai Viteazu Avenue, 300 222 Timisoara, Romania.
Polymers (Basel). 2020 Mar 11;12(3):640. doi: 10.3390/polym12030640.
Selective Laser Sintering is a flexible additive manufacturing technology that can be used for the fabrication of high-resolution parts. Alongside the shape and dimension of the parts, the mechanical properties are essential for the majority of applications. Therefore, this paper investigates dimensional accuracy and mode I fracture toughness (K) of Single Edge Notch Bending samples under a Three Point Bending fixture, according to the ASTM D5045-14 standard. The work focuses on the influence of two major aspects of additive manufacturing: material type (Polyamide PA2200 and Alumide) and part orientation in the building environment (orientations of 0°, 45° and 90° are considered). The rest of the controllable parameters remains constant for all samples. The results reveal a direct link between the sample densities and the dimensional accuracy with orientation. The dimensional accuracy of the samples is also material dependent. For both materials, the angular orientation leads to significant anisotropic behavior in terms of K. Moreover, the type of material fundamentally influences the K values and the fracture mode. The obtained results can be used in the development of additive manufactured parts in order to obtain predictable dimensional tolerances and fracture properties.
选择性激光烧结是一种灵活的增材制造技术，可用于制造高分辨率零件。除了零件的形状和尺寸外，机械性能对于大多数应用来说至关重要。因此，本文根据ASTM D5045 - 14标准，研究了三点弯曲夹具下单边切口弯曲试样的尺寸精度和I型断裂韧性（K）。这项工作重点关注增材制造两个主要方面的影响：材料类型（聚酰胺PA2200和铝化物）以及构建环境中零件的方向（考虑0°、45°和90°方向）。所有样品的其余可控参数保持不变。结果揭示了样品密度与尺寸精度随方向之间的直接联系。样品的尺寸精度也取决于材料。对于这两种材料，角度方向在K方面导致显著的各向异性行为。此外，材料类型从根本上影响K值和断裂模式。所获得的结果可用于增材制造零件的开发，以获得可预测的尺寸公差和断裂性能。
