The field of High Entropy Alloys (HEAs) offers the possibility to develop tailored alloy compositions for a range of different applications, including as braze filler metals (BFMs). Potential advantages include the ability to avoid the formation of intermetallic phases and tailoring gap filling properties. However, there is limited knowledge of how HEAs perform as a BFM during vacuum brazing which is critical in understanding their applicability for industrial use. In this work we present the results of wetting and vacuum brazing trials using several different, high temperature HEA compositions on Alloy 718 substrates, selected with a number of potential industrial applications in mind. The HEA compositions were all NiFeCr based, with each distinct HEA having different proportions of these, as well as containing other elements such as Ga, Ge and B. The wettability, microstructure and mechanical properties of the resultant joints were investigated and compared against a range of commercially available BFMs (both nickel based and iron based). The Ni-based BFMs were selected to include a range of different melting point depressant elements (e.g. B and Si).
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