Feasibility Study on Additive Manufacturing of Inconel 625 and Aluminum Bimetallic Parts
摘要
Inconel 625, a renowned nickel superalloy, is highly regarded for its remarkable corrosion resistance at elevated temperatures. In contrast, Aluminum alloys are known for their lightweight attributes and superior thermal conductivity. Combining these materials in a bimetallic component offers the potential to harness their distinctive strengths. Conventional techniques for joining dissimilar metals, like friction stir welding and metal arc gas welding, come with inherent limitations. These methods often result in the formation of brittle intermetallic compounds (IMCs) and residual stresses due to the substantial heat input involved. The current research focuses on studying the deposition of Inconel 625 onto an Aluminum 6061 substrate using two advanced technologies—laser-based directed energy deposition (DED) and cold metal transfer (CMT)-based wire arc additive manufacturing (WAAM). For study purposes, single-track and multi-layer depositions of Inconel 625 onto Aluminum 6061 were carried out using a laser-based DED machine and WAAM processes with varying energy densities. The observations of the fabricated specimens unveiled several challenges, including the initiation of cracks and delamination during deposition at higher temperatures due to the difference in thermal conductivity between Inconel 625 and Aluminum 6061. Additionally, the high reflectivity of Aluminum to laser, its exceptional thermal conductivity, and the formation of intermetallic compounds between Aluminum and nickel at the deposition zone further aggravated the complexity of the process. In summary, the article aims to provide valuable insights on the feasibility and potential advantages of employing additive manufacturing to achieve bimetallic printing of Inconel 625 onto Aluminum 6061 which can potentially back innovations in more prominent industries such as aerospace and marine.