| The wear of machine parts exist universally, they cause huge energy loss of energy and material. Wear reduces mechanical device's performance, the reliability as well as the service life seriously. Martensitic stainless steel coating arc sprayed can effectively repair worn parts, strengthen the surface performance of material, enhances mechanical device's service life. Moreover, the technology of arc spraying martensitic stainless steel is also used in the many kinds of rapid tool manufactures.Four kinds of different carbon amount martensitic stainless steel, 1Cr13, 3Cr13, 4Cr13 and 7Cr13, were employed in this experiment. They were sprayed by using different arc spraying technological parameter to obtain the corresponding coating separately. Through the tests of the coating samples with a wet sand oak rubber wear testing and a sand blasting installation separately, the influence of arc spraying technological parameter on coating's wear resistance was studied. Using the method of tin soldering, silver brazing and TIG welding, the weldability of 4Cr13 stainless steel coatings were studied, and the suitable technology for welding of the coatings were looked for. By means of SEM, the microarea power spectrum analysis as well as the XRD analysis, the microstructure of spraying martensitic stainless steel coating and welded joints' microstructure of coating were investigated and analyzed in this article. And, the bonding strength between coating and substrate, bonding strength of welded joints, the tensile strength of coating itself as well as the Vickers hardness of coating were measured.The results showed that with the increasing of the spraying current, the wear resistance of the coatings was getting higher, the increasing of the spraying voltage could decrease the wear resistance of the coatings and the increasing of the spraying distance could also decrease the wear resistance. It also revealed that with the increase of the spraying distance, the Vickers hardness of the coatings descended and that the more carbon content in the wire, the better wear resistance the coatings had with the same spraying parameter. Polished coating surface could significantly improve the brazing process performance. Silver brazing could well joint the carbon steel substrate and the stainless steel coating polished. Spraying a layer of carbon coating on the coating surface of martensitic stainless steel could be benefit to the tin soldering's reliability of coating. The tensile strengths of the joints were more than those among the layers of the coatings. The bonding strength between 4Cr13 coatings and substrate were equally 26.9MPa, the tensile strength of coatings were 129.95MPa equally. With the same spraying technological parameter, the higher the carbon amount of wire, the higher the hardness of coating. The average hardness of 7Cr13, 3Cr13 and 1Cr13 coating was separately about 439.88HV, 379.01HV, 281.08HV.
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