Mechanical Properties and Microstructure of IN738LC Nickel Superalloy Castings

Abstract:

IN738LC is a cast nickel-base superalloy developed for applications requiring high strength at elevated temperatures. Its balanced composition provides a good combination of tensile and creep-rupture properties as a result of gamma prime precipitate strengthening enhanced by solid solution and grain-boundary strengthening. Experimental castings are used in heat treated state. This alloy is used widely, for example, for manufacturing of gas turbine blades. Recently, customers demand different weight of castings hence different conditions during solidifying and cooling of the castings originate, resulting in different castings microstructure. When approving the castings, mechanical values are measured by tensile test on test bars made from the cast blade roots. This work investigates mechanical properties casting structure correlations, particularly grain, casting defects, carbides.

• Periodical: Materials Science Forum (Volume 782)
• Pages: 437-440
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.782.437
• Online since: April 2014
• Authors: Jiří Zýka*, Irena Andršová, Božena Podhorná, Karel Hrbáček
• Keywords: Mechanical Property, Microstructure, Nickel Superalloy

References

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DOI: 10.2320/matertrans.45.562

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