Effect of NiCrBSi content on microstructural evolution, cracking susceptibility and wear behaviors of laser cladding WC/Ni–NiCrBSi composite coatings

摘要: Abstract Ni-based composite coatings were produced on the Ti6Al4V substrate by laser cladding 30 wt.% WC/70 wt.% (Ni–NiCrBSi). The microstructural evolution and mechanical properties investigated in details. results indicated that coating (70 wt.% Ni) was mainly composed of WC TiC as reinforcements, α(Ti), TiNi Ti 2 Ni matrix. Two new phases (W, Ti)C 3 B formed (21 wt.% Ni–49 wt.% NiCrBSi). When content NiCrBSi further increased to 63 wt.% 70 wt.%, matrix transformed into , uniformity also improved. As contents varied (0 wt.%, 49 wt.%, 63 wt.%, 70 wt.%), average microhardness gradually (745 HV 0.1 976 1046 1107 ), however fracture toughness presents opposite change trend (4.20 MPa m 1/2 3.57 MPa m 3.02 MPa m 2.92 MPa m ). Wear mechanism changed from micro-cutting mixture brittle debonding, debonding. appropriate addition (21 wt.%) 30 wt.%WC-NiCrBSi material favorable improvement wear resistance coating.