Effect of alloy elements on iridium shear modulus by Ab initio analysis.
Zhengguang Liu1,2, Panlong An3, Gao Wang4
1Department of Public Basis, Zhaoqing Medical College, No. 6 Xijiang South Road, Zhaoqing, 526020, China.
Journal of Molecular Modeling
|September 22, 2021
Summary
Adding Rh, Re, W, Au, and Pt to iridium (Ir) reduces its brittleness by lowering the shear modulus. This study quantizes the impact of these elements on iridium
Area of Science:
- Materials Science
- Computational Materials Science
- Solid State Physics
Background:
- Iridium (Ir) is a face-centered cubic metal with potential applications requiring high mechanical properties.
- Understanding alloying effects on mechanical properties like shear modulus is crucial for material design.
Purpose of the Study:
- To investigate the influence of alloying elements (Rhodium, Rhenium, Tungsten, Gold, Platinum) on the shear modulus of face-centered cubic Iridium.
- To determine how these additions affect the brittleness of Iridium.
Main Methods:
- Utilized ab initio computational methods to calculate the shear modulus.
- Determined shear modulus via the second derivative of strain energy with respect to strain.
Main Results:
- Addition of Rh, Re, W, Au, and Pt decreased both the bulk modulus (G) and the shear modulus to bulk modulus ratio (G/B) of Iridium.
- All five alloying elements were found to reduce the inherent brittleness of Iridium.
- The decreasing order of shear modulus varied between crystalline directions [112] and [100], influenced by atomic distance and bond strength.
Conclusions:
- Alloying Iridium with Rh, Re, W, Au, and Pt effectively reduces its brittleness.
- The reduction in brittleness is primarily attributed to the decreased shear modulus.
- Atomic distance and interatomic bond strength are key factors governing the observed changes in shear modulus.
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