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TiN as a new type of ceramic material, density, hardness, good electrical conductivity, anti-wear, anti-oxidation and corrosion, excellent performance, very suitable tool, mold and bearing surface of the coating material. Therefore, of TiN hard coatings prepared much attention of researchers. Double glow plasma surface alloying technology, ion permeability in the the Q235 steel surfaces prior period Ti, the formation of hundreds of microns of titanium solid solution diffusion layer, the late pass nitrogen synthesis of TiN, a direct form TiN Permeation Layer and its surface microstructure observation, and scanning electron microscopy (SEM), energy spectrum ingredients, surface hardness, X-ray diffraction (XRD) analysis. Found Penetration TiN infiltration titanium stage and the synthesis stage process parameters, obtained under controlled conditions of various process parameters TiN Permeation Layer phase structure, surface morphology, surface composition, appearance, microhardness variation. Infiltration of the TiN coating sample, untreated Q235 steel the sample T10 quenching and tempering sample, and 3Cr13 nitriding sample under the same conditions, the wear resistance test; the the seepage coating sample with untreated the Q235 steel and 1Crl8Ni9Ti of stainless steel sample l mol / L H2SO4 solution, 3.5% NaCl solution and 4% NaOH solution, respectively electrochemical corrosion comparison test. The results are as follows: (1) double glow plasma surface alloying of TiN coatings on Q235 Steel TiN Permeation Layer. TiN Permeation Layer Synthesized double glow plasma process parameters: the the infiltration the Ti stage process parameters: ultimate vacuum to 3Pa; working gas Ar; Working pressure 25 to 35 Pa; around source voltage-1000V; trial about the kind of voltage-600V; the sample holding temperature 1050 ° C; time 2h. Synthesis stage of the process parameters: working gas Ar and N2; working gas pressure of 25 ~~ 35 Pa; source voltage-1000V; specimens voltage - 400V; specimen holding temperature 1050 ° C; time 2 h; Ar/N2 flow ratio 8:1. (2) With the TiN Permeation Layer thickness increases, Permeation Layer gradually transformed by the {100} oriented growth of {111} oriented growth, to be obtained with higher hardness and better wear resistance of TiN Permeation Layer, required to obtain {111} preferred orientation of the TiN phase. (3) With the TiN Permeation increase in thickness of the coating, the surface of the cellular morphology increasingly obvious and outward protrusion \TiN Permeation the plating surface morphology was uniform and dense Cellular organization, high hardness, appearance is also more uniform and smooth, with no loss. (4) source voltage sample voltage of the Titanizing stage, the synthesis stage sample voltage synthesis stage holding time on the surface of the coating of TiN Permeation Ti N ratio of the number of atoms is not large, gas pressure, holding temperature and Ar / N2 flow rate is larger than its impact. As the working pressure increases, Ti, N atomic number ratio gradually increases; the higher the temperature of incubation, TiN coating penetration surface of Ti, N atomic ratio of the greater; the Ar/N2 flow ratio of 8:1, Ti N the number of atoms of 1:1 than the nearest surface Ti, the N atomic number ratio approaches 1:1, TiN the seepage coating the better the performance. (5) When the TiN Permeation Layer thin surface color tends to pale yellow. When you select this paper the optimum, TiN permeability coating is golden brown and not peeling. TiN Permeation coating surface changes color along with a variety of different parameters, and its essence is different because the phase content, golden TiN Permeation Layer contains ε-TiN phase up to the highest microhardness. (6) TiN permeability coating thickness have a greater impact on the permeability coating phase structure, surface morphology, surface composition, appearance and hardness, TiN permeability coating is too thick or too thin is not conducive to the best of the infiltration coating . (7) TiN infiltration coating surface morphology of the \TiN Permeation Layer TiN particles uniformly distributed diffusion layer and the surface TiN deposition layer. TiN Permeation coating composition, hardness and structure showed a gradient distribution. Infiltration coating thickness 16μm, and the substrate to form a solid metallurgical layer, combined with high strength. (8) under the same wear conditions, TiN infiltration coating relatively minimal wear rate increased by 7.81 times more abrasion resistance than untreated Q235 steel samples; increased by 5.625-fold compared to the T10 steel quenched and tempered specimen; over 3Cr13 stainless steel nitrided trial like increase of 7 times. With grit degree increases, TiN infiltration coating relative wear rate increases greater; loads, TiN infiltration plating more wear mass loss, the greater the relative wear rate. Infiltration plating wear failure mainly in the form of chipping and spalling, micro-cutting is a slight, almost no plastic deformation. With sand increased, fragmentation and spalling of the degree gradually deepened. In this article experimental conditions, TiN infiltration of wear mechanism of the coating stress fatigue. (9) l mol / L H2SO4 solution, TiN infiltration coating resistant to corrosion than untreated Q235 steel increased 11.5 times and 2.65 times higher than 1Crl8Ni9Ti stainless; infiltration in 3.5% NaCl solution, TiN coating corrosion increased by 11.3 times more performance than the untreated Q235 steel, but somewhat less than 1Crl8Ni9Ti stainless steel. TiN Permeation Layer acid solution corrosive than salt water corrosion strong; 4% NaOH solution, TiN infiltration of the corrosion resistance of the coating than untreated Q235 steel increased 27.8 times, and 1Cr18Ni9Ti stainless steel corrosion resistance quite.
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