Influence of H-Content on Thermo-Mechanical Properties of NiAl Alloys

Abstract:

The effect of Hydrogen on thermo-mechanical properties and performance of metals and alloys are of critical importance. In recent years, the relevance of H-metal interactions has been broadened into functional metallic compounds and alloys as they find use in energy and medical applications. Here, we aim to assess the influence of H-content on thermal, physical, chemical, and mechanical properties on Nickel-Aluminum alloys using Molecular Dynamics (MD) and Density Functional Theory (DFT) methods. We report studies on Ni₃Al, Al₃Ni, AlNi with H-content ranging from 1% to 10% at elevated temperatures for different structures such as B1, B2, L10, A4 and random and ordered in L12 to establish enthalpy-temperature-concentration, volume-temperature concentration, volume-pressure-concentration relationships. From these relationships we derive thermodynamic and mechanical properties such as thermal expansion, bulk modulus and Young modulus.

• Periodical: Materials Science Forum (Volume 915)
• Pages: 224-228
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.915.224
• Online since: March 2018
• Authors: Uğur Aslan*, Tahir Çağın
• Keywords: Hydrogen in Metals, NiAl Alloys, Thermomechanical Properties

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