Strukturní stabilita heterogenních svarových spojů oceli P91

Structural stability of dissimilar weld joints of steel P91

článek v časopise - ostatní, Jost

en

This paper addresses the issue of C and N redistribution in weld joints of creep-resistant chromium steels. The redistribution of C and N was measured using the wave-dispersive X-ray method. The conditions of the long-term diffusion annealing process were: temperature 575, 625 and 700 oC; time 10, 100, 1 000 and 5 000 hours. It was ascertained that C and N diffused from the low-alloy steels to the high-alloy steel P91. The carbon diffusion coefficients in the individual steels of 15128/P91 and SK3STC/P91 weld joints, the ratio between the thermodynamic activity coefficients of carbon in joints, the diffusion interaction parameters , and their temperature dependencies were estimated from carbon concentration curves. The paper also contains a microstructure analysis of decarburized and carburized zones in the weld joints studied.

Tento článek pojednává o redistribuci C a N ve svarových spojích žárupevných ocelí. Redistribuce C a N byla měřena metodou EPMA. Podmínky dlouhodobého žíhání byly následující: teplota 575, 625 and 700 C; čas 10, 100, 1 000 and 5 000 h. Bylo potvrzeno, že C a N difundují z nízkolegovaných ocelí do vysokopevné oceli P91. Článek také obsahuje rozbor mikrostruktury oduhličených a nauhličených oblastí ve studovaných svarových spojích.

This paper addresses the issue of C and N redistribution in weld joints of creep-resistant chromium steels. The redistribution of C and N was measured using the wave-dispersive X-ray method. The conditions of the long-term diffusion annealing process were: temperature 575, 625 and 700 oC; time 10, 100, 1 000 and 5 000 hours. It was ascertained that C and N diffused from the low-alloy steels to the high-alloy steel P91. The carbon diffusion coefficients in the individual steels of 15128/P91 and SK3STC/P91 weld joints, the ratio between the thermodynamic activity coefficients of carbon in joints, the diffusion interaction parameters , and their temperature dependencies were estimated from carbon concentration curves. The paper also contains a microstructure analysis of decarburized and carburized zones in the weld joints studied.

structural stabilidy, creep-resistant steels, weld joints, redistribution of C and N

2002

01.01.2002

1362-1718

Science and Technology of Welding and Joinig

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