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Studied structural engineering materials at high sulfur corrosion behavior of the atmosphere in industrial production is very important. 310 stainless steel in high temperature oxidizing environment is widely used in heat-resistant steel. In this paper, thermal gravimetric analysis (TG), optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy with energy spectrum (SEM / EDX), and electron probe microanalysis (EPMA), was studied in 310 stainless steel high-sulfur, low oxygen atmosphere temperature corrosion, powder coating and multi-arc ion plating coating on 310 stainless steel corrosion resistance to high temperature and high-temperature corrosion mechanism of influence. Hopes to develop suitable high temperature corrosion resistance of stainless steel 310 coating. Current systems for the conversion of coal and CS 2 reactors and other contacts sulfur media device design, requirements to provide an atmosphere of sulfur alloy corrosion data. 310 stainless steel was studied at a temperature and pressure sulfur corrosion problems, especially of chemical composition on curing. At 700 ℃, 10000h long 310 stainless steel running in a large number of grain boundary precipitates σ phase, causing the Cr depleted near the grain boundary, resulting in corrosion along the grain boundaries. 310 stainless steel at 550 ~ 650 ℃, atmospheric pressure, 0.5% SO 2 / S 2 / 2.0% N 2 and 2.3% SO < sub> 2 / S 2 / 8.8% N 2 oxidation under the conditions of high temperature / curing behavior. Experiments show that: 310SS corrosion rate increases with increasing temperature: When the temperature is the same, the atmosphere V S2 / V SO2 increases, the corrosion rate also increased but little change. Corrosion products can be divided into three layers: the outer layer is made Fe 1-x S, NiO and a small amount of Fe 2 O 3 composition, porous, brittle, flaky, black; intermediate layer of mountains FeCr 2 S 4 and a small amount of Cr 2 O-3 composition; inner thin, discontinuous, the NiCr 2 S 4 , a small amount of Cr 3 S 4 and Cr 2 S 4 components. Outer layer of the Fe, Ni outward diffusion of; the intermediate layer and the inner mountain O, S inward diffusion of. Corrosion kinetics parabola. The oxide - sulfide intermediate layer composed of the mixed product more dense, the control of the mass transfer play a major role. At 600 ℃, an atmospheric pressure of 2.3% SO 2 / S 2 / 8.8% N 2 atmosphere, solid infiltration Al, B- Al and B after the first infiltration infiltration Al three kinds of coatings were significantly improved resistance to high temperature sulfur corrosion (after which the first B penetration effect is most obvious infiltration AI): B penetration resistant coating to improve the substrate temperature gas corrosion little effect; Solid samples of seepage MO *. Element has only a small amount of solid solution in the matrix surface, which deteriorate the corrosion resistance of the material. Multi-arc plating method from within the 310 stainless steel substrate were plated on a M. , Nb, AI, NbAI, MO-Al @ film and explores the different process parameters such as: a substrate bias voltage, arc current and plating time) on the coating composition, coating thickness. Study of the above five kinds of coated samples at 600 C for 2.3% SO / / 8.8% N Grand total pressure of fat called 'Flying atmosphere environment corrosion behavior. Experiments show that: the five kinds of coated samples were corrosion kinetics followed a parabolic law. Plated MO, Nb, Nb-AI film samples corrosion resistance of stainless steel than the matrix argument 0 Poor; while plating Sichuan, M. A pair of thin films of corrosion worries in the matrix material. That during the etching of the corrosion product formed coating layer, the macroscopic defects Zhong: cracks, porosity) is the emergence of the main reasons that the corrosion rate increases.
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