Search results for "Electropolishing"
showing 4 items of 4 documents
Comparison of electropolishing behaviours of TSC, ALM and cast 316L stainless steel in H 3 PO 4 /H 2 SO 4
2017
Abstract In recent decades, new manufacturing processes have been developed such as Thermal Spray Coating (TSC) and Additive Layer Manufacturing (ALM), which reduce or avoid machining of parts with complex geometries. This study aims to develop an Electropolishing (EP) process for TSC and ALM 316L Stainless Steel (SS). EP is an anodic dissolution process currently used in industry to reduce surface roughness and obtain a bright and smooth finish. The EP mechanism was studied, in a mixture of H3PO4 and H2SO4, for TSC, ALM and “cast” SS in order to determine the best conditions (time, temperature, potential). Special attention was paid to surface characterization by combining several techniqu…
Influence of long-term ageing in solution containing chloride ions on the passivity and the corrosion resistance of duplex stainless steels
2011
Abstract The influence of long-term ageing in NaCl on the passivity and the electrochemical behavior of UNS S32304 is studied. The passive film thickness, the Cr/Fe ratio and the chloride content were significantly increased after ageing. The chloride distribution depends on residual stresses, sample microstructure and surface preparation. Local electrochemical measurements revealed that pitting potentials are between 250–550 mV vs. SCE after electropolishing. The higher the chloride content, the lower the local pitting potential. It was also shown that the presence of chloride was balanced by the enrichment in chromium after ageing. Then no pitting potential could be measured.
Electropolishing of CuZn brasses and 316L stainless steels: Influence of alloy composition or preparation process (ALM vs. standard method)
2016
International audience; In the present paper, electropolishing behavior of different brass alloys (CuZn39Pb2, CuZn42) in phosphoric acid is studied to observe the impact of alloying elements on polishing quality. In the same way, the influence of the manufacturing process is also evaluated through the comparison of a “standard” stainless steel and a stainless steel prepared by Additive Laser Manufacturing (ALM). An electrochemical study was first performed to determine the best treatment conditions for each material/electrolyte pair and to study the electropolishing mechanism and its kinetic dependence on diffusion. Metallic samples are fully characterized before and after electropolishing …