Characteristics of in-flight particles and splats thermally sprayed by using conventional and nano-composite cored wires

Abstract

Characteristics of in flight particle and splat fabricated by arc spraying of three different types of cored-wire including WC-Cr-Ni, WC-Cr-Fe and W-Cr-Fe nano-composite were revealed. Inflight particles and splats were deeply characterized in order to correlate their characteristics that forming coating and affecting coating structure and properties. Starting cored-wires were also characterized prior to being sprayed. Particle size, morphology microstructure, chemical composition and phase identification were investigated through various techniques. The results showed that the size of the in-flight particle did not depend mainly on the size of filler particles as expected, but was instead strongly related to the whole content of metallic phase composed the cored-wire, as the more metal composition the larger size of the in-flight obtained. Splat shapes and characteristics were also found to depend on the metal content; a flower shape splat with a high degree of splashing was predominant for cored-wire having more metal composition. The W-Cr-Fe nano-composite cored wire had the highest content of metallic binder phase, which resulted in the largest in-flight particles produced, and well melted of the metallic phase led to the highest degree of splashing observed.