Surface characteristics of plasma-sprayed Al ₂ O ₃ and Cr ₃ C ₂ coatings on IS2062

The present investigation focuses on the deposition of ceramic Al 2 O 3 and Cr 3 C 2 materials on IS2062 steel surface by employing plasma spray approach with varied standoff distance, powder feed and current. Central composite design of response surface method is organized to accomplish the coating experimentation. The mechanical characteristics were evaluated in terms of adhesion strength and microhardness. The influence of coating parameters on evaluated responses has been detailed. The microscopic features of the coated surface, and roughness characteristics were studied using Scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS), and Atomic force microscopy (AFM) techniques. The findings on Cr 3 C 2 coatings showcased higher order of strength while Al 2 O 3 surfaces exhibited higher microhardness. SEM examination unveiled effective adhesion and bonding between Al 2 O 3 -IS2062 and Cr 3 C 2 -IS2062 surfaces. Porosity and roughness studies revealed better mechanical interlocking and partial melting of powder particles between the surfaces. The Al 2 O 3 coatings portray an optimal adhesion strength and microhardness of 41.77 ± 18 MPa and 1103.33 ± 100 HV, respectively. Also, ideal adhesion strength and microhardness are 76.03 ± 16 MPa and 891 ± 109 HV for Cr 3 C 2 coatings. The optimal values obtained closely align with the experimental results, as demonstrated by the conformity test.