Change of the Chromium and Iron Concentration at Nitriding of Ferrochromium in Solid State

摘要

5.1. Concentration fields of the chromium and iron in the area nitride + solid solution are obtained by the help of X-ray microanalyser "Superprobe 733". The results show that chromium content in the nitride is higher (83.56%) and iron content is less than the average one for the alloy (5.36%). In the solid solution the iron content is higher (29.87 - 30.70%) and chromium is less than the average for the alloy (66.01 - 68.22%), Figure 4 and 5. 5.2. The distribution of chromium and iron concentrations in the matrix in dependence on the distance from the surface through that nitrogen diffuses is obtained. Near to the surface chromium content is 25.38% and iron content is 69.67%. The chromium and iron concentrations are equal with the average for the alloy on a distance 300 - 400 μm from the surface of nitriding 5.3. The obtained qualitative results for the distribution of the chromium and iron can be used for clarifying the mechanism of the diffusion processes in double alloys, containing one nitride forming element. The present work is supported by Project TN 1007/2000, financed by the NATIONAL SCIENCE FUND to the Ministry of Education and Science of Republic of Bulgaria.