Laser processing as a high-throughput method to investigate microstructure-processing-property relationships in multiprincipal element alloys

A direct laser deposition processing method was applied to construct compositional and microstructural libraries of Al_xCoCrFeNi in an efficient and high-throughput manner. Among the compositions (x = 0.51–1.25) and quench rates (26–6400 K/s) studied, most of the laser deposited alloys exhibit a cellular microstructure, similar to the cast materials. The microstructural feature sizes were found to follow a power law relationship with the quench rate. The dependence of the microhardness on microstructural length scale was also investigated and observed to follow a Hall-Petch relationship. This study indicates that laser processing is an effective method for rapidly and efficiently evaluating multiprincipal element alloys and their microstructures.