| Due to its low cost,high strength,high hardness,excellent soft magnetic properties and abrasion resistance,amorphous alloys have attracted extensive attention from many scholars.But the amorphous alloy itself has the defects of high brittleness,poor toughness,and high cooling rate,so its size is limited,which limits its industrial application.By heating and cooling the powder onto the substrate in the way of thermal spraying,the amorphous alloy can break through the size limit.On the other hand,because the cooling rate of thermal spraying is very fast,the microstructure characteristics and excellent properties of the amorphous alloy can be retained,which will effectively improve the application of amorphous alloy in the industrial field.Thermal spraying process can not only repair the damaged parts,but also improve the corrosion resistance,wear resistance and other properties,and can correct the size deviation caused by machining errors.In this paper,the WC-10Co-4Cr/Fe-based amorphous composite coating was prepared by supersonic plasma spraying on C45 steel.The main research results are as follows:（1）The addition of WC-10Co-4Cr does not affect the amorphous formation ability of Fe-based amorphous alloys.The WC-10Co-4Cr/Fe-based amorphous composite coating is relatively dense,and its porosity is lower than that of single Fe-based amorphous coating.At the same time,the addition of WC-10Co-4Cr can effectively improve the surface hardness of the coating and reduce the porosity of the coating.（2）The experimental results of reciprocating friction and sliding wear show that the 9 wt.%WC-10Co-4Cr/Fe-based amorphous composite coating shows the best wear resistance,and its wear rate is only 1/4 of that of the single Fe-based amorphous coating under the same experimental conditions.The wear mechanism of the coating changes from mild fatigue wear to severe fatigue wear with the increase of load,accompanied by oxidation wear.（3）In 3.5 wt.%Na Cl solution,the corrosion potential of WC-10Co-4Cr/Fe-based amorphous composite coating is higher,the corrosion current density is lower,and the coating can be well protected in the corrosive medium,showing excellent corrosion resistance.The 9wt.%WC-10Co-4Cr/Fe-based amorphous composite coating has the best corrosion performance,and its polarization resistance is 7975.94Ω·cm2,which is about 3 times that of the single Fe-based amorphous coating 2547.84Ω·cm2.（4）The erosion-corrosion test results show that the erosion resistance of WC-10Co-4Cr/Fe-based amorphous composite coating is better than that of single Fe-based amorphous coating,and the erosion rate of 9 wt.%WC-10Co-4Cr/Fe-based amorphous composite coating is the lowest,about 1/7.5 of that of single Fe-based amorphous coating.In the erosion process,when the erosion Angle is 0°,the friction between the quartz sand particles and the coating surface is mainly carried out in the form of scraping,and the wear mode is plowing. |
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