The Paton Welding Journal, 2001, №04

2001 №04 (02)

2001 №04 (04)

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The Paton Welding Journal, 2001, #4, 13-17 pages

Effect of structural changes in high-temperature heating on ductile characteristics of nickel alloys

A.V. Zvyagintseva, K.A. Yushchenko, V.S. Savchenko

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

Abstract
Investigation of hot ductility of alloy IN 840 proves that it has three characteristic ductility temperature ranges. Drastic fall in ductility takes place in a narrow temperature range. It results from melting of grain boundaries to form on them small amounts of the liquid films. The data of metallography and fractography obtained on welded samples show that fracture at high temperatures occurs along the boundaries of grains (dendrites) rich in alloying elements and is of the same nature as fracture of the base metal at high temperatures.
Keywords: heat-resistant nickel alloys, hot ductility, fracture mechanism, nil ductility temperature, melting of grain boundaries, chemical heterogeneity, enrichment of boundaries, dendrites

References

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Suggested Citation

A.V. Zvyagintseva, K.A. Yushchenko, V.S. Savchenko (2001) Effect of structural changes in high-temperature heating on ductile characteristics of nickel alloys. The Paton Welding J., 04, 13-17.

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