Carbon redistribution during long-term operation of weld joints of creep-resisting chrome steels (in Czech) MILLION, B., FORET, R., REK, A., STRANSKY, K. vol. 37 (1999), no. 5, pp. 314 - 323
Abstract The paper deals with C and N redistribution in weld joints of creep-resisting chrome steels. The C and N redistribution were measured by means of wave-disperse X-ray method. The condition of long-term diffusion annealing were realised as follows: temperature 575, 625 and 700 °C; time 10, 100, 1000 and 5000 hours. It was estimated that C and N diffused from the low alloy steels to the high alloy steel P91. The errors of the measured nitrogen concentration curves were so high that the quantitative evaluation of nitrogen concentration curves was impossible. The carbon diffusion coefficients in individual steels of 15128/P91 and SK3STC/P91 weld joints, the ratio between thermodynamic activity coefficients of carbon in joints, diffusion interaction parameters ßCrC, and their temperature dependences have been estimated from the measured carbon concentration curves. Key words carbon and nitrogen redistribution, weld joints of steels, carbon diffusion coefficient, thermodynamic and diffusion interaction parameters chromium-carbon Full text not available
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