The Comparison Of The Mechanical And Wear-resistent Properties Of Detonation Sprayed WC13Ni4Cr And WC10Co4Cr Coatings

In this paper,two kinds of WC-13Ni4Cr and WC-10Co4Cr coatings were deposited by the detonation-sprayed technology.The mixture of acetylene and propane was employed as the combustion fuel gas.The relative phase content of W2C and W in the coatings was calculated by an XRD quantitative analysis method,which offers a convenient way to compare the decomposition degree of WC under different spraying conditions.Wear resistances of the as-sprayed coatings were compared by a rolling wear method.Hardness,elastic modulus,and fracture toughness of coatings were evaluated.The adhesion strength of coatings was obtained by the pull-off method.Corrosion resistance of the two kinds of coatings was compared in different corrosion medium.In order to further improve the coating quality,the influences of substrate temperature on the adhesion strength,flattening behavior of particles,weibull modulus and characteristic hardness of microhardness were evaluated.The results indicate that the decomposition of WC particles in both coatings decrease remarkably,however,the mechanical properties and wear resistance of coatings were obviously improved when increasing the flow rate of propane.The wear resistance of the two kinds of coatings is substantially improved and even reaches the same level when increasing the propane flow rate to 40 slpm.In terms of the same corrosion environment,WC13Ni4Cr coating has better corrosion resistance than that of WC-10Co4Cr in the solution of NaCl and NaOH.Increasing the starting deposition temperature of substrates can enhance the characteristic hardness and the adhesion strength of WC-10Co4Cr coatings.Meanwhile,the obtained higher weibull modulus of coating hardness indicates that WC-based coatings could have more homogeneous microstructure.