Elastic moduli and thermal expansion coefficients of medium-entropy subsystems of the CrMnFeCoNi high-entropy alloy

G. Laplanche , P. Gadaud (1) , C. Bärsch , K. Demtröder , C. Reinhart , J. Schreuer , E.P. George

1 ENDO - ENDOmmagement et durabilité [Institut Pprime]

Elastic moduli of a set of equiatomic alloys (CrFeCoNi, CrCoNi, CrFeNi, FeCoNi, MnCoNi, MnFeNi, and CoNi), which are medium-entropy subsystems of the CrMnFeCoNi high-entropy alloy were determined as a function of temperature over the range 293 K–1000 K. Thermal expansion coefficients were determined for these alloys over the temperature range 100 K–673 K. All alloys were single-phase and had the face-centered cubic (FCC) crystal structure, except CrFeNi which is a two-phase alloy containing a small amount of body-centered cubic (BCC) precipitates in a FCC matrix. The temperature dependences of thermal expansion coefficients and elastic moduli obtained here are useful for quantifying fundamental aspects such as solid solution strengthening, and for structural analysis/design. Using the above results, the yield strengths reported in literature for these alloys were normalized by their shear moduli to reveal the influence of shear modulus on solid solution strengthening.

Mots clés: High entropy alloys; CoCrFeMnNi; Microstructure; Texture; Thermal expansion coefficient; Elastic constants

Domaines: Mécanique des fluides [physics.class-ph]; Matériaux et structures en mécanique [physics.class-ph]; Acoustique [physics.class-ph]; Automatique / Robotique; Electromagnétisme; Milieux fluides et réactifs; Energie électrique; Thermique [physics.class-ph]; Vibrations [physics.class-ph]; Physique mathématique [math-ph]; Physique Quantique [quant-ph]; Acoustique [physics.class-ph]; Biomécanique [physics.med-ph]; Matériaux; Polymères

G. Laplanche, P. Gadaud, C. Bärsch, K. Demtröder, C. Reinhart, et al.. Elastic moduli and thermal expansion coefficients of medium-entropy subsystems of the CrMnFeCoNi high-entropy alloy. Journal of Alloys and Compounds, 2018, 746, pp.244-255. ⟨10.1016/j.jallcom.2018.02.251⟩. ⟨hal-02369793⟩