Zhao Bo, Liu Yuanlin, Kang Qingyuan, Zhao Junjie, Ma Guangyu, Wang Jie
School of Material Science and Engineering, Shandong Jianzhu University, Jinan 250101, China.
Research Institute of Materials Reliability for Advanced Equipments, Shandong Jianzhu University, Jinan 250101, China.
Materials (Basel). 2024 Dec 31;18(1):127. doi: 10.3390/ma18010127.
Wire-arc additive manufacturing (WAAM) has fully empowered the design and manufacturing of metals with its unparalleled efficiency and flexibility. However, the process has relatively poor shape control capabilities, often requiring machining post-processing. This study explores a tungsten inert gas arc remelting (TIGAR) process to improve the surface flatness of WAAM components at a low cost and significantly reduce machining waste (up to 76%), which is crucial for the sustainable development of the process. The extent of surface improvement under different remelting currents was investigated. A detailed discussion was held on the mechanism by which the remelting arc, along with its molten pool, improves surface flatness. The robustness and adaptability of the process in a rough production environment were examined. And the impact of the process on the microstructure and hardness of the additive part's surface was examined. Through systematic and quantitative analysis, it was found that within a certain range, the improvement effect on flatness increases with the increase in remelting current; when the remelting current reaches 80 A, it can significantly reduce the maximum height difference (65%) and the standard deviation of surface height (66%), and the remelting effect is uniform and reliable. TIGAR has a flattening effect on both the protrusions and depressions of the additive part's surface. Proper overlap of remelted passes is crucial for the improvement of surface flatness. If the spacing of remelted passes is changed or the direction of remelting is adjusted, it is necessary to ensure the width of the molten pool to achieve sufficient overlap between adjacent remelted passes.
电弧增材制造（WAAM）凭借其无与伦比的效率和灵活性，为金属的设计与制造赋予了强大动力。然而，该工艺的形状控制能力相对较差，通常需要进行机加工后处理。本研究探索了一种钨极惰性气体电弧重熔（TIGAR）工艺，以低成本提高WAAM部件的表面平整度，并显著减少加工废料（高达76%），这对该工艺的可持续发展至关重要。研究了不同重熔电流下的表面改善程度。详细讨论了重熔电弧及其熔池改善表面平整度的机理。考察了该工艺在粗糙生产环境中的稳健性和适应性。并研究了该工艺对增材部件表面微观结构和硬度的影响。通过系统的定量分析发现，在一定范围内，平整度改善效果随重熔电流的增加而增强；当重熔电流达到80A时，可显著降低最大高度差（65%）和表面高度标准差（66%），且重熔效果均匀可靠。TIGAR对增材部件表面的凸起和凹陷均有平整作用。重熔道适当重叠对于提高表面平整度至关重要。若改变重熔道间距或调整重熔方向，需确保熔池宽度，以实现相邻重熔道之间的充分重叠。
