Multi‐material parts can offer valuable solutions to engineering problems when compared to single materials. The conceptualization of a multifunctional Inconel 718 (IN718)–Copper (Cu) solution aims to improve the heat extraction capacity of an aerospace component. High‐strength IN718 was used as the base material and highly thermal conductive Cu was employed for internal cooling channels. The cooling channels are produced by electrical discharge machining (EDM) and subsequently filled with Cu to be sintered by hot pressing (HP). The morphological, microstructural, hardness, and thermal properties of the hot‐pressed multi‐material IN718–Cu specimens are studied to evaluate the feasibility of HP processing as a viable manufacturing approach for these multi‐material solutions. The multi‐material IN718–Cu specimens presents a well‐defined design with good metallurgical bonding between the two materials and a thin diffusion region is found, assuring the final properties of each individual material. The Vickers’ microhardness of IN178 and Cu are in accordance with the reported for conventional processes which indicates good densification. The thermal conductivity of the multi‐material IN718–Cu specimen is 25% higher than mono‐material IN718, which can be a significant improvement in the thermal efficiency of an aerospace component.
13 May 2022 in Materials and Manufacturing Processes
In this study, samples of 420 stainless steel were obtained by hot pressing from powder at temperatures from 1,100 to 1,200°C. The aim was to explore the influence of the processing temperature on their grain size, microstructure, densification and mechanical properties. The results showed that it is possible to produce dense samples at these sintering temperatures. The sintering temperature influenced the density, grain size, structural phases, and hardness of the samples. Martensite and austenite were present in the samples sintered at 1,100, 1,150, and 1,180°C. Precipitation of Cr23C6 was observed after sintering at 1,200°C. This sample was the one with the highest density (99.7% densification) and hardness (771.9 HV).