Characterization and High-Temperature Oxidation Behavior of Ni–20Cr Deposits Fabricated by Cold Spray-Based Additive Manufacturing

Abstract

Hot corrosion is a critical problem in a wide range of high-temperature applications. Ni–20Cr alloy is frequently used in such applications owing to its good hot-corrosion resistance. In the current work, thick Ni–20Cr plates in a thickness range of 6–10 mm were fabricated using cold spray-based additive manufacturing (CSAM). High-pressure cold spraying was used with nitrogen as the propellant gas. Pre- (substrate heating, SH) and post-heat treatments (hot isostatic pressing, HIP) were also performed to comprehend the changes in the deposit properties. The deposits were subjected to microstructural and mechanical characterization to explore the potential of cold spraying for CSAM of Ni–20Cr standalone products. The cold-sprayed plates were successfully developed without any oxide formation. HIP treatment was found to be useful to reduce porosity. The cold-sprayed substrate-heated Ni–20Cr deposits exhibited excellent oxidation resistance at a high temperature of 900 °C.

Development, Characterization and High-Temperature Oxidation Behaviour of Hot-Isostatic-Treated Cold-Sprayed Thick Titanium Deposits

“…Selective laser melting (SLM) was developed to eliminate the post-processing of SLS-fabricated components. In addition to laser-based processes, quite a few other techniques have been developed, such as electron beam melting and ultrasonic consolidation [2][3][4][5][6]. However, these techniques are yet to attract significant importance due to the inherent limitations like poor surface quality, low adhesion and low production volumes [7].…”

Flow Visualization and Parameter Suitability in Cold Spray Titanium Deposition: A CFD Approach

“…A broad range of metals, including Cu, Al, Ti, Fe-and Ni-based alloys, as well as ceramics and cermets, can be deposited on a wide variety of substrate materials. As the deleterious effects of thermal distortions and heat affected zones (HAZ) are very minimal, it is a very reliable technology for coating temperature-sensitive materials such as amorphous and nanomaterials, and different powder material combinations with varied differences in their melting point temperatures [2,3,4]. The powder particle velocity at the exit of the nozzle immediately before hitting the substrate is a paramount characteristic in the cold spray method.…”