Processing and characterization of Inconel 718/Al₂O₃ nanocomposite powder fabricated by different techniques

Inconel 718/Al₂O₃ nanocomposite powders produced by sonication-assisted high-energy ball milling (HEBM) and mechanofusion processes are presented and compared. Powders were pre-mixed via sonication in ethanol. Two pre-mixed batches were processed by HEBM using two different cooling temperatures and milling times. To investigate the influence of Al₂O₃ on the mechanical milling stages, Inconel 718 powder without alumina was also mechanically milled. Results show that the tested methods are able to produce Inconel 718/Al₂O₃ composite with suitable characteristics for further manufacturing or functionalization. A homogeneous dispersion of nanosized alumina throughout the metal matrix was only achieved by milling, showing a monomodal particle size distribution, with controlled both morphology and composition. Low cooling milling temperatures reduce Inconel 718/Al₂O₃ composite production time using less mechanical energy during milling. Sonication-assisted HEBM is an adequate method for the fabrication of non-commercial nanocomposites to be used as raw material in different manufacturing techniques.