Impact of short range ordering on the anomalous four-stage strain hardening behavior of low solid-solution hardening Ni–Cr alloys

Abstract Solid solution hardening in high entropy alloys was studied for the Cantor alloy using diffusion couples and nanoindentation. We study a continuous variation of the alloying content and directly correlate the nanoindentation hardness to the local composition up to the phase boundary. The composition dependent hardness is analysed using the Labusch model and the more recent Varvenne model. The Labusch model has been fitted to experimental data and confirms Cr as the most potent strengthening element. For comparison of the experimental hardness and the predicted yield strength of the Varvenne model, a concentration-dependent strain-hardening factor is introduced to account for strain hardening during indentation, which leads to a very good agreement between experiment and model. A study of the input parameters of the Varvenne model, performed by atomistic computer simulations, shows no significant effect of fluctuations in the atomic size misfit volumes or in the local shear modulus to the computed yield strength. Graphic Abstract

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Saturated solid-solution hardening behavior of Ir–Hf–Nb refractory superalloys for ultra-high temperature applications

Scripta Materialia ◽

10.1016/j.scriptamat.2005.08.038 ◽

2006 ◽

Vol 54 (1) ◽

pp. 115-119 ◽

Cited By ~ 13

Author(s):

J.B. Sha ◽

Y. Yamabe-Mitarai

Keyword(s):

Solid Solution ◽

High Temperature ◽

Solid Solution Hardening ◽

Solution Hardening ◽

Hardening Behavior ◽

Ultra High Temperature ◽

Temperature Applications

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Effect of Ta addition on microstructure and mechanical properties of dual two-phase Ni3Al-Ni3V intermetallic alloy–Retraction

MRS Advances ◽

10.1557/adv.2019.140 ◽

2019 ◽

Vol 4 (25-26) ◽

pp. 1509-1514 ◽

Cited By ~ 1

Author(s):

Kazushige Ioroi ◽

Yasuyuki Kaneno ◽

Takayuki Takasugi

Keyword(s):

Solid Solution ◽

Volume Fraction ◽

Intermetallic Alloy ◽

The Other ◽

Solid Solution Hardening ◽

Solution Hardening ◽

Two Phase ◽

Atomic Size ◽

Microstructural Observation ◽

Hardening Behavior

ABSTRACTMechanism for the hardening of two-phase Ni3Al-Ni3V intermetallic alloy to which 2 at.% Ta was added in different substitution manners for Ni, Al and V was presented, based on the microstructural observation, alloying behavior and lattice properties of the additive in the constituent phases. The hardening behavior was explained in terms of solid solution hardening in which the mixture rule in the volume fraction of the two constituent phases and the atomic size misfit evaluated from the changes of the lattice parameters were incorporated. Consequently, the hardening for the alloys in which the additives were substituted for Ni and V was attributed to solid solution hardening. On the other hand, the hardening for the alloy in which the additive was substituted for Al was attributed to the hardening due to microstructural refining in addition to the solid solution hardening.

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A Tem Study of Slip Systems in MoSi2/WSi2 Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089020 ◽

1991 ◽

Vol 49 ◽

pp. 942-943

Author(s):

Stuart A. Maloy

Keyword(s):

Solid Solution ◽

Solid Solution Hardening ◽

Slip Systems ◽

High Melting ◽

Group 14 ◽

Solution Hardening ◽

Brittle To Ductile Transition ◽

High Melting Temperature ◽

Tetragonal Unit Cell ◽

Structural Applications

MoSi2 has recently been investigated as a potential material for high temperature structural applications. It has excellent oxidation resistance up to 1700°C, a high melting temperature, 2030°C, and a brittle-to-ductile transition temperature at 900-1000°C. WSi2 is isomorphous with MoSi2 and has a body-centered tetragonal unit cell of the space group 14/mmm. The lattice parameters are a=3.20 Å and c=7.84 Å for MoSi2 and a=3.21 Å and c=7.88 Å for WSi2. Therefore, WSi2 was added to MoSi2 to improve its strength via solid solution hardening. The purpose of this study was to investigate the slip systems in polycrystalline MoSi2/WSi2 alloys.

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