Failure analysis of laser cladding layer in coal mine environment
In order to solve the problem of corrosion failure of laser cladding layer of oil cylinder in coal mine environment,the mine en-vironment such as underground water,pulverized coal immersion liquid water,coal quality and other mine environments was analyzed,the microstructure of the cladding layer was studied by metallographic microscope,the corrosion state and chemical elements of the clad-ding layer were studied by SEM images,EDS energy spectrum,XPS and other means,and the corrosion mechanism of the cladding layer in the coal mine environment was discussed.The results show that the cladding layer and the matrix metallurgical combination are good,and no defects are found inside.The tissues are distributed in dendritic crystals and elliptical and granular shapes,and the closer to the matrix,the smaller the dendrites.The depth of the corrosion pit is about 50-150 μm,which can reach 1/4 of the thickness of the clad-ding layer,and the size is different.The chemical composition of the cladding layer is uniform,the element content meets the design re-quirements,and there is no obvious element segregation.EDS spectroscopy,XPS and other test results showed that the corrosion started from the chromium-poor region between the dendrites of the cladding layer,and the elements such as S and Cl participated in the corro-sion process.Pitting and contact corrosion between pulverized coal containing corrosive media such as S and Cl and the cladding layer leads to the failure of the cladding layer,which provides a reference for the surface treatment process design of oil cylinders in coal mine environment.
万方数据
维普
