WAAM process for metal block structure parts based on mixed heat input
WAAM process for metal block structure parts based on mixed heat input
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DOI：
10.1007/s00170-021-06654-x
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发表时间：
2021-01-26
影响因子：
3.4
通讯作者：
Pan, Zengxi
中科院分区：
文献类型：
--
作者：
Cui, Junyi;Yuan, Lei;Pan, Zengxi
基于机器人焊接的增材制造通过应用电弧作为热源和焊丝作为原料来制造金属零件。该工艺称为电弧增材制造 (WAAM)。然而，由于工艺复杂且缺乏适当的工艺规划方法，当前的WAAM工艺在制造具有高几何精度和一致焊接的块状结构部件方面存在局限性。此外，空隙、间隙和塌陷等常见缺陷会降低最终产品的机械性能。本文提出了一种基于混合热输入（MHI）策略的新颖工艺规划方法，以最大限度地减少制造大型块结构部件时出现的空隙和塌陷缺陷，同时保持高制造效率。通过将每一层分为边界层和内层，MHI 方法在层的不同位置应用各种热输入条件，从而能够构建无缺陷的组件。该方法的性能在被视为常规结构部件的制造的验证研究中得到了展示。为了评估沉积样品的机械性能，报告了硬度和微观结构，并与传统 WAAM 工艺进行比较。然后，将MHI策略应用于与验证研究结构相似的大型块结构部件的制造。此外，通过两个案例研究评估了所提出的 MHI 策略在制造复杂几何零件方面的稳健性。结果表明，该策略成功地同时实现了高生产效率和高质量。
Additive manufacturing based on robotic welding is used for the manufacture of metal parts by applying an arc as a heat source and wire as feedstock. The process is known as wire arc additive manufacturing (WAAM). However, the current WAAM process has a limitation in fabricating block structure components with high geometry accuracy and consistent welding due to the process complexity and the lack of appropriate process planning methods. Furthermore, common defects such as voids, gaps, and collapse decrease the mechanical properties of the final product. This paper presents a novel process planning method based on a mixed heat input (MHI) strategy to minimize voids and collapse defects that occur in fabricating large block structure components while maintaining a high manufacturing efficiency. By separating each layer into boundary layers and inner layers, the MHI method applies various heat input conditions at different positions of the layer allowing the construction of defect-free components. The performance of this method is shown in a validation study considered as the fabrication of a regular structure component. To evaluate the mechanical properties of the deposited sample, the hardness and microstructure are reported and compared with the conventional WAAM process. Then, the MHI strategy is applied to the manufacturing of a large block structure component with a similar structure as the validation study. Furthermore, the robustness of the proposed MHI strategy in fabricating complex geometric parts is evaluated by two case studies. The results show that such strategy succeeds in achieving high production efficiency and quality simultaneously.