Rezumat
The aim of the work is to develop a technology for the electrode materials production from “colmonoy-WC” alloys and hard alloys using TiC, WC, Mo2C, TiN, Co, Cr, Ni, and Al. Their phase composition and structure, mass-transfer kinetics, hardness and wear-resistance of electric-spark coatings made of the developed alloys were studied. The methods used included metallography and electron microscopy, X-ray phase and durometric analysis. In the “colmonoy” (Ni-Ni3B-Si-Cu), “colmonoy-10% WC” and “colmonoy-25% WC” alloys the structure of the eutectic type was observed. When the WC content in the alloys is higher, the structure that seems to be a conglo-merate of the phases of solid solution on the base of nickel and wolfram carboborosilicide was observed. At 7.5 J impulse energy, the thickness of the formed coatings was 3–4 mm. Wear-resistance of the coatings magnifies with increasing the WC content in the coatings from 64.5 μm/km for “colmonoy” up to 18.5 μm/km for 70% WC alloy, and steel wear-resistance in these conditions is 160 μm/km. It was determined that the structure and composition of the developed electrode materials from the solid alloys on the base of carbides TiC and WC allows for obtaining electro-spark coatings with the thickness up to 100 μm and hardness of 20–24 GPa. The mass of the transferred material is significantly higher than at using standard alloys Т15К6 and ТН–20. The developed materials are recommended for strengthening and renovation of the constructional steel worn parts by the electric-spark method.
Keywords: electro-spark strengthening, renovation, electrode materials, erosion properties, coating properties, wear resistance.