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Indexed by:Journal Papers

Date of Publication:2020-05-01

Journal:CRYSTALS

Included Journals:SCIE

Volume:10

Issue:5

ISSN No.:2073-4352

Key Words:laser cladding; high-entropy alloy coating; Ti-6Al-4V; wear resistance

Abstract:CoCrFeNi2V0.5Tix high entropy alloy coatings were synthesized by laser cladding on Ti-6Al-4V (annotated as TC4) substrate. The microstructures, hardness, and wear properties of the coatings were studied in detail. The results showed that these coatings were all composed of body-centered cubic (BCC) solid solution, (Co,Ni)Ti-2 phase, and Ti-rich phase. With the increase of Ti content (x in the range of 0-1.0), the hardness of these coatings (about 960 HV) was basically unchanged and stabilized, whereas, when x was increased to 1.25, the correspondent hardness was decreased significantly to about 830 HV. Compared with original substrate, the wear resistance of high-entropy alloy (HEA) coatings was greatly improved. In particular, CoCrFeNi2V0.5Ti0.75 (donated as Ti0.75) exhibited the lowest wear rate, width, and depth of tracks of wear, indicating the best wear resistance. Moreover, the wear mechanisms of Ti0.75 coating were mainly adhesive wear and oxidative wear.