The high‐temperature oxidation resistance of thin‐walled ingots of Ni₃Al alloys with directional grain structure

Abstract

Purpose

This paper describes the changing of high‐temperature oxidation resistance (HTOR) at the temperature 1,200°C which is dependant on characteristics of alloying and microstructure. The aim of the research was to show a broad problem of using the intermetallic Ni₃Al in the production of propulsion aircraft engines because this material has a very high HTOR and low density.

Design/methodology/approach

For the estimation of a level of HTOR of Ni₃Al (Ni‐12Al) and its alloying compositions, a method was used in which samples were heated in ambient atmosphere at 1,200°C for a period of 1,500 h. The samples were weighed every 100 h. The data was obtained for eight different compositions.

Findings

The process of researching indicated that a maximum HTOR has the composition Ni‐12Al without alloying which is obtaining by dosed directional solidification (DDS) method and having the largest structural stability at 1,200°C.

Practical implications

This material is broadly used in the production of valves, electrical heaters, etc. However, these details are obtained by equiaxial casting or powder metallurgy methods. The material obtained by DDS method has higher strength characteristics and may be implicated in many components of aircraft engines (elements of the firing chamber or a stationary blades, etc.).

Originality/value

This research presents a new type of microstructure which has a matrix Ni₃Al on a base of disordered gamma phase (DDS Method). Currently, this structure has had little studies carried out on it. However, it could become an object for detailed research for process phase precipitation using a super high magnifications.

Citation

Verin, A.S. and Verin, M.A. (2005), "The high‐temperature oxidation resistance of thin‐walled ingots of Ni₃Al alloys with directional grain structure", Anti-Corrosion Methods and Materials, Vol. 52 No. 4, pp. 233-236. https://doi.org/10.1108/00035590510603274