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With the rapid development of modern industry, the level of mold production technology as a measure of the level of a country's manufacturing an important indicator of the performance of the mold which put forward higher requirements, the life issues have become increasingly prominent. Most damage to the mold from the surface of the beginning, it must further strengthen the mold surface, visible research and application of advanced surface modification technology to improve die life, cost and productivity has a very important significance. Surface modification of the existing mold technology, TD (Thermal Diffusion) Bath Chromizing technology because of its simple equipment, easy operation, high production capacity, low cost way of cooling the workpiece can be arbitrarily chosen, etc., is considered to be the mold ideal surface modification technologies. The authors TD Chromizing cold mold material was discussed research process, first through comparative studies arrive at a more satisfactory Bath Chromizing formula, then the effects of different process parameters on the coating thickness were investigated. X-ray diffraction analysis (XRD), energy spectrum analysis and other modern means of cladding tissue morphology, phase structure of systematic research and analysis, and coating hardness, wear resistance and other performance more systematic testing. Through pilot studies and comprehensive analysis, the following conclusions: 1. Consider coating thickness, bath volatility and liquidity and other factors, the use of ((68.4BaCl2 7.6NaCl) 10Cr2O3 10NaF 4Al) salt formulation, T10 steel in chromizing under lower temperatures. Chromized coating layer consists Cr7C3 phase and a small amount of (Cr, Fe) 7C3 phase composition, coating thickness, a metallurgical bond with the substrate. 2 of Cr12, T10 and TD Chromizing GCr15 material that the thickness of the base coating layer removing \Rate play hindered; same process conditions, coating thickness and infiltration rate with increasing temperature and the extension of time showed an increasing trend. 3 coating layer surface microhardness values ??2000HV0.05 above, and with the increase in the matrix hardness and chromized time, the coating layer surface hardness increasing trend; chromized sample shows a cross-sectional microhardness, cladding hardness and hardness of the matrix is ??more gentle transition between. 4 Chromizing cladding material surface can greatly improve the performance Abrasive, worn surface morphology showed, compared with other test materials, TD Chromizing wear scar surface of the specimen thin and shallow, only a portion of cladding off, indicating that the coating layer and the substrate in good metallurgical bond. On the cladding surface microhardness indentation analysis shows that the integrity of the indentation morphology, creasing number of peripheral and inner cracks cladding and the substrate on the support has a direct effect, indicating that the TD CHROMIZED toughening treatment on the substrate improve and enhance the compressive cladding and anti-spalling properties have a positive effect. 5 Chromizing coating with good resistance to high temperature oxidation resistance, heat-treated at 800 ℃, TD coating microhardness still amounted to 2017 HV0.05. 6. Chromizing coating with excellent resistance to acid corrosion, corrosion test shows the surface morphology, TD chromized the matrix material than the sample present on the surface and fewer shallow pits, exhibit good corrosion resistance. These findings for TD Chromizing cold die steel surface modification and its application has important reference value.
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