基于主应力轨迹线的熔融沉积成型填充路径优化

Infill Toolpath Optimization for Fused Deposition Modeling Based on Principal Stress Lines

摘要:

以熔融沉积成型（fused deposition modeling， FDM）为代表的增材制造层间与层内的各向异性严重影响零件机械性能。提出一种基于主应力轨迹线（principal stress lines， PSL）引导，通过设计FDM层内填充路径使其与载荷路径相协调以提高零件机械性能的方法。给出了基于有限元分析的主应力轨迹线生成方法和基于Grasshopper的主应力轨迹线可视化方法；提出了基于主应力轨迹线种子线的区域路径生成算法，并开发了自定义路径转换G代码的工艺平台；进行了拉伸和三点弯曲力学试验。结果表明基于主应力轨迹线的填充路径相比传统的0°方向和90°方向的填充路径，拉伸试样的抗拉强度分别提升了8.33%和19.74%，弯曲试样的抗弯强度分别提升了11.46%和20.47%。

Abstract:

Anisotropy in strength between layers and filaments in fused deposition modeling （FDM） additive manufacturing has a significant influence on mechanical properties of fabricated objects. A method was proposed to improve mechanical properties of the part by the design of the infill toolpath to make it in alignment with the load paths under the guidance of principal stress lines （PSL）. The PSL generation method based on finite element analysis and the PSL visualization method based on Grasshopper were presented. The region toolpath generation algorithm based on PSL seed lines and the toolpath-to-Gcode conversion method were put forward. Tensile and three-point bending mechanical tests were carried out. Compared with the traditional infill toolpaths in the 0°and 90° direction， the tensile strength of the PSL-based printed specimens increased by 8.33% and 19.74%， and the bending strength of the PSL-based printed specimens increased by 11.46% and 20.47%， respectively.