Langelandsvik Geir, Akselsen Odd M, Furu Trond, Roven Hans J
SINTEF Industry, Richard Birkelands veg 2B, 7034 Trondheim, Norway.
Norsk Hydro, Corporate R&D Headquarter, 0283 Oslo, Norway.
Materials (Basel). 2021 Sep 17;14(18):5370. doi: 10.3390/ma14185370.
Processing of aluminum alloys by wire arc additive manufacturing (WAAM) gained significant attention from industry and academia in the last decade. With the possibility to create large and relatively complex parts at low investment and operational expenses, WAAM is well-suited for implementation in a range of industries. The process nature involves fusion melting of a feedstock wire by an electric arc where metal droplets are strategically deposited in a layer-by-layer fashion to create the final shape. The inherent fusion and solidification characteristics in WAAM are governing several aspects of the final material, herein process-related defects such as porosity and cracking, microstructure, properties, and performance. Coupled to all mentioned aspects is the alloy composition, which at present is highly restricted for WAAM of aluminum but received considerable attention in later years. This review article describes common quality issues related to WAAM of aluminum, i.e., porosity, residual stresses, and cracking. Measures to combat these challenges are further outlined, with special attention to the alloy composition. The state-of-the-art of aluminum alloy selection and measures to further enhance the performance of aluminum WAAM materials are presented. Strategies for further development of new alloys are discussed, with attention on the importance of reducing crack susceptibility and grain refinement.
在过去十年中，电弧增材制造（WAAM）铝合金的工艺受到了工业界和学术界的广泛关注。由于能够以低投资和运营成本制造大型且相对复杂的零件，WAAM非常适合在一系列行业中应用。该工艺的本质是通过电弧将原料丝材熔化，金属熔滴以逐层方式有策略地沉积，从而形成最终形状。WAAM中固有的熔化和凝固特性决定了最终材料的几个方面，这里包括与工艺相关的缺陷，如气孔率和裂纹、微观结构、性能和表现。与上述所有方面相关的是合金成分，目前铝合金的WAAM合金成分受到很大限制，但在近年来受到了相当多的关注。这篇综述文章描述了与铝合金WAAM相关的常见质量问题，即气孔率、残余应力和裂纹。进一步概述了应对这些挑战的措施，特别关注合金成分。介绍了铝合金选择的最新技术以及进一步提高铝合金WAAM材料性能的措施。讨论了新型合金进一步发展的策略，关注降低裂纹敏感性和细化晶粒的重要性。
