The Paton Welding Journal, 2006, №11

2006 №11 (02)

2006 №11 (04)

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The Paton Welding Journal, 2006, #11, 13-16 pages

Features of δ-ferrite formation on the fusion boundary in welding heat-resistant chromium martensitic steel

V.Yu. Skulsky

E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.

Abstract
Possible mechanism of formation of decarburized δ-ferrite grains in the fusion zone was studied by simulating the thermodeformation cycle of welding in a rigidly-restrained sample of heat-resistant steel P91 through heating with passing electric current up to surface melting, and by comparing the resulting structure with that of the actual welded joints. The suggested mechanism attributes formation of the above grains to appearance of regions depleted in carbon and rich in ferritizing elements, which results from liquation redistribution of alloying and impurity elements, as well as regions depleted in carbon in the grain bulk, resulting from its migration towards the weld
Keywords: chromium martensitic steel, welded joints, fusion zone, grain surface melting, liquation, carbon diffusion, δ-ferrite

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Suggested Citation

V.Yu. Skulsky (2006) Features of δ-ferrite formation on the fusion boundary in welding heat-resistant chromium martensitic steel. The Paton Welding J., 11, 13-16.

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