Oxinitrocarburizing in Fluidized Bed Technology Applied to Drawing Steels
Abstract
Steels oxinitrocarburizing is a thermochemical treatment in order to obtain a slight increase of mechanical properties associated with increased of corrosion resistance. The paper is based on experiments performed on a plant with fluidized bed. Environment for oxinitrocarburizing is achieved by means of fluidized solid granules sorted by size ranging within 0.10-0.16 mm, resulting from decomposing a gas mixture of methane and ammoniac (initially). Samples are used in low carbon steels. Controlled oxidation is performed at a temperature of 570 °C with superheated water vapor. The results confirm the possibility to obtain layer structure and to increase surface mechanical properties.
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References
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