Phase stabilization and oxidation of a continuous composition spread multi-principal element (AlFeNiTiVZr)1-xCrx alloy

JOURNAL OF ALLOYS AND COMPOUNDS

卷:861

Article

Ruiz-Yi, Benjamin^1,2  Williams, Travis^1,2  Bunn, Jonathan Kenneth³  Ren, Fang⁴  Al Hasan, Naila⁵  Takeuchi, Ichiro⁵  Hattrick-Simpers, Jason⁶  Mehta, Apurva⁴ 

[1] Univ South Carolina, Dept Chem Engn, Columbia, SC 29208 USA

[2] Univ South Carolina, SmartState Ctr Strateg Approaches Generat Elect, Columbia, SC 29208 USA

[3] AccuStrata Inc, Rockville, MD 20852 USA

[4] SLAC Natl Accelerator Lab, Stanford Synchrotron Radiat Lightsource, Menlo Pk, CA 94025 USA

[5] Univ Maryland, Dept Mat Sci & Engn, College Pk, MD 20742 USA

[6] NIST, Gaithersburg, MD 20899 USA

关键词: Metals and alloys;    Thin films;    Optical spectroscopy;    X-ray diffraction;    Phase transitions;    Oxidation;   

DOI  :  10.1016/j.jallcom.2020.158565

来源: Elsevier

【 摘 要 】

Multi-Principal Element Alloys (MPEA) have been hypothesized to maintain a stable single alloy phase and resist corrosion at high temperatures, which are desirable in various functional applications, including material of turbine blades. However, studies into oxidation resistant alloys have been constrained to individual MPEA systems or a limited selection of compositions within those systems. Here, High-Throughput Experimental (HTE) techniques were utilized to rapidly assess phase stability and resistance to oxidation of an (AlFeNiTiVZr)(1-x)Cr-x continuous composition spread (CCS) thin-film alloy system. High-throughput synchrotron diffraction and Raman spectroscopy were used to identify phases, especially high symmetry structures and oxides, as a function of annealing time and composition. The formation of two distinct phase regions, R-1 and R-2, across the CCS was observed. One of these phase regions, R-2, exhibited a stable high symmetry BCC-like phase at Cr concentrations greater than 25.4 at%, and grew a passivating mixed metal surface oxide; whereas, the R-1 phase region, decomposed on oxidation to multiple oxides and reacted with the substrate to form silicides. The passivating mixed metal oxide layer appears to prevent destabilization of the (AlFeNiTiVZr)(1-x)Cr(x)MPEA BCC solid solution. At longer annealing times the passivating phase was seen only above 29.2 at% Cr. High Cr-doped (AlFeNiTiVZr)(1-x)Cr-x appear to be a good candidate for high temperature, oxidation-resistant structural alloys. (C) 2020 Published by Elsevier B.V.

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