| In this paper,two kinds of alloy coatings of Ni-4.1W-11.3P and Ni-4.9W-5.9P were prepared by chemical deposition way and the coating composition,organizational structure and microscopic characteristics were studied by XRD,SEM/EDS,metallographic observation and test methods and Jade quantitative analysis software.The wear mechanism of the coating on two annealing modes was discussed and the main conclusion is as follows:?1?The nanocrystalline crystals of the high P coating is higher than the middle coating,whether in the heat treatment of the stove or the laser heat treatment.?2?In the middle coating,the Ni3P crystal granules precipitate the formation of the crystalline nickel ratio:the hardness of the middle coating is higher than the high P coating before the rise of I Ni/I total?volume?.When the temperature increases,phosphate content of ascension,Ni3P grain size in the ratio of plating:INi3P/I total reaches the maximum value?volume?,coating hardness in maximum.At the same scanning speed,the hardness fluctuation middle coating is larger than the high P coating.?3?The best wear and wear properties of two coatings is treated by laser heat treatment rather than furnace heat treatment.The wear characteristics of the coating and the main wear form is related to nano grain structure,including INi/Itotal namely amorphous nickel content?volume?and INi3P/Itotal namely Ni3P grain content?volume?,Ni3P grain size,crystallization degree and plating voids.?4?Compared with the conventional heat treatment the laser heat treatment can make Ni-W-P coating have better wear resistance and short processing time and control processing areas without affecting the surrounding area.So to speak,in addition to the high cost,laser surface heat treatment is an ideal way to achieve a specific location of the local coating nano performance improvement without affecting the substrate performance and is suitable for the base board of low melting point and high heat sensitive materials. |
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