Solid-solution strengthening in refractory high entropy alloys

Autor(es)

Coury, Francisco Gil ^{[1, 2]} ; Kaufman, Michael ^[2] ; Clarke, Amy J. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Rod Washington Luis, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[2] Colorado Sch Mines, George S Ansell Dept Met & Mat Engn, 1500 Illinois St, Golden, CO 80401 - USA

• Tipo de documento: Artigo Científico
• Fonte: ACTA MATERIALIA; v. 175, p. 66-81, AUG 15 2019.
• Citações Web of Science: 3

Resumo

Compression stress-strain curves of a number of refractory high entropy alloys (RHEAS) were generated at temperatures ranging from room temperature to 1000 degrees C. It is shown that solid-solution strengthening in these alloys has both an athermal and a thermal component. Results from mechanical testing are combined with literature data to develop solid-solution strengthening models for both components that incorporate the particularities of single-phase body centered cubic (BCC) materials. The athermal component is affected by a combination of atomic size mismatch and elastic modulus mismatch, which depend upon average values from each alloy, thereby allowing this component to be estimated in a high throughput fashion. On the other hand, the thermally-activated yield stress component does not correlate with any parameter that can be calculated by averaging pure elemental atomic properties and it is observed to be larger than the values found for pure BCC refractory metals and their dilute alloys. Overall, RHEAS are found to have larger thermal and athermal yield stress components compared to pure or conventional refractory alloys, which explains their relatively high strengths at room temperature. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 18/08778-4 - Design e Produção de Ligas de Alta Entropia com Elevada Resistência Mecânica e Tenacidade para Aplicações como Revestimentos em Ambientes Extremos
• Beneficiário: Francisco Gil Coury
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado