Microstructure, Hardening, and Mechanical Properties of Hypoeutectic Al–Ce–Ni Alloys with Zr and Zr + Sc Additions and the Effect of Ultrasonic Melt Processing

Abstract

Ternary Al‐Ce‐Ni alloys have a potential in the manufacture of automotive and airspace components, as well as in replacing traditional aluminum alloys in high‐temperature applications, which is determined by the formation of fine and thermally stable Al11Ce3 and Al3Ni eutectic. In this study we successfully improved the microstructure and mechanical properties of a hypoeutectic Al4Ce2Ni alloy by using Zr and Zr+Sc additions combined with ultrasonic melt processing and dispersion hardening. As a result, the grain structure of the as‐cast alloys was significantly refined and the annealing at 350 °C led to a considerable hardening effect, especially in the alloys with Zr+Sc additions (doubling the hardness). Al3Zr and Al3(Zr,Sc) coherent particles were identified as hardening nano‐precipitates. The compressive mechanical testing at room and elevated temperatures showed that the additions of Zr and Zr+Sc improved the strength with the additional increase caused by ultrasonic melt processing.This article is protected by copyright. All rights reserved.