Microstructure and wear properties of WC particle reinforced composite coating on Ti6Al4V alloy produced by the plasma transferred arc method

• Published in: Applied surface science 2013-06, Vol.274, p.334-340
• Main Author: CELIK, Osman Nuri
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Physics; Plasma transferred arc; Ti6Al4V; Wear
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2013.03.057

•WC particle reinforced composite coatings were produced on Ti6Al4V alloy by plasma transferred arc method.•All PTA processes performed at 70A, 80A, and 90A increased the surface hardness and the wear resistance of the alloy.•The composite coating produced at 70A exhibited better wear resistance than the coatings produced at 80A and 90A. The microstructure and wear properties of a WC particle reinforced composite coating produced by the plasma transferred arc (PTA) method on Ti6Al4V alloy were investigated in this study. PTA processing was carried out using argon as the plasma gas at arc current values of 70A, 80A and 90A. Scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were used to characterize the microstructure of the composite layer formed on the surface of a Ti6Al4V substrate. The results indicate that the WC, TiC and W2C carbide phases formed in the composite layers produced by PTA on the surface of the Ti6Al4V alloy. The distributions and volume fractions of these phases were found to vary with the arc current values. Wear tests were performed under dry sliding conditions using a linear ball-on-disc geometry. The microhardness and wear resistances of all of the composite layers produced by the PTA process were enhanced relative to those of the Ti6Al4V substrate. The homogeneity and volume fractions of the carbide phases in the composite layers were responsible for the improvement in the wear resistance of the alloy. The wear test results indicate that the alloy modified at 70A shows better wear resistance than the alloys modified at 80A and 90A.