Structure Stability of Ni-Base and Co-Base Alloys

Abstract:

This article summarises results of structure stability investigation of cast Ni-base and Co-base alloys after prolonged high temperature exposure at 900-1100 °C. Cast Ni (Co)-Cr-W-C alloys are resistant to high-temperature corrosion, due to high chromium content. Their heat resistance is caused by presence of carbides, which are stable at very high temperatures. Carbides precipitate in shape of large plate-like particles or carbide eutectics at casting cell boundaries, thus forming carbide skeleton of the alloy. Carbide morphology and temperature stability depends on chemical composition of the alloy, e.g. carbide content, type and content of carbide-forming elements. Microstructure changes were evaluated by stereological analysis and X ray-spectral microanalysis.

• Periodical: Materials Science Forum (Volume 782)
• Pages: 431-436
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.782.431
• Online since: April 2014
• Authors: Božena Podhorná, Irena Andršová, Jana Dobrovská, Vlastimil Vodárek, Karel Hrbáček
• Keywords: Carbide, Cast Ni-Base Alloy, High Temperature Annealing, Structure Stability

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DOI: 10.14505/despag.2014.ch7

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