【摘 要】
：
In order to study the spray conditions and original powders on the microstructure, phase composition and property of HVOF WC-Co coating, the WC-17Co coatings were sprayed by using different HVOF syste
【机 构】
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Jiangxi R&D Center on Remanufacture Engineering of Materials Surface, Jiujiang University, Jiujiang
【出 处】
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第十一届全国表面工程大会暨第八届全国青年表面工程学术会议
论文部分内容阅读
In order to study the spray conditions and original powders on the microstructure, phase composition and property of HVOF WC-Co coating, the WC-17Co coatings were sprayed by using different HVOF systems and spraying parameters, and by using the powders with different particle size and WC size. The microstructure and phase composition of the coatings were examined by SEM and XRD, respectively. The WC, W2C, W and W3Co3C were quantitatively characterized by evaluation its peak intensity in the XRD pattern. The coating porosity was also quantitatively evaluated through the image analysis of the cross section SEM photos by using the image J software. In addition, the microhardness, fracture toughness and abrasive wear were tested by using the indentation method and pin-on-disc method, respectively. In order to explore the dominant effect of microstructure and phase constitution, the correlations between phase composition and properties of as sprayed WC-Co coating was examined. The worn surface morphology was also observed to characterize the two-body abrasive wear behavior of the coatings. The experimental results revealed that the content of the W3Co3C phase possesses dominant effect on the fracture toughness and abrasive wear of the coatings. The powder particle size has the prominent effect on the coating phase constitutions in addition to the propane flow and WC particle size. The porosity of the coating exerts some effect on coating microhardness. The abrasive wear of the coatings happens in two forms, one is the gouging and peer off of the carbide particles, second is the peer off of the splats.
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