Structural, elastic and thermal properties of cementite (Fe$_3$C) were studied using a Modified Embedded Atom Method (MEAM) potential for iron-carbon (Fe-C) alloys. Previously developed Fe and C single element potentials were used to develop an Fe-C alloy MEAM potential, using a statistically-based optimization scheme to reproduce structural and elastic properties of cementite, the interstitial energies of C in bcc Fe as well as heat of formation of Fe-C alloys in L$_{12}$ and B$_1$ structures. The stability of cementite was investigated by molecular dynamics simulations at high temperatures. The nine single crystal elastic constants for cementite were obtained by computing total energies for strained cells. Polycrystalline elastic moduli for cementite were calculated from the single crystal elastic constants of cementite. The formation energies of (001), (010), and (100) surfaces of cementite were also calculated. The melting temperature and the variation of specific heat and volume with respect to temperature were investigated by performing a two-phase (solid/liquid) molecular dynamics simulation of cementite. The predictions of the potential are in good agreement with first-principles calculations and experiments.
Multiphysics analysis of acoustically actuated nanospherical antennas embedded in polymer/metal medium with magneto-electro-elastic surface/interface effects
Mechanical, elastic and thermodynamic properties of crystalline lithium silicides
采用密度泛函理论和基于修正嵌入原子的力场方法对锂硅化物(LixSiy)的晶体热力学稳定相进行了研究,并与实验结果进行了比较.基于分子动力学的MEAM方法为大晶胞晶体结构的热力学性质计算提供了一个快速、准确的计算框架。除了包括Li、Li 12 Si 7、Li 7Si 3、Li 13 Si 4、Li 15 Si 4、Li 21 Si 5、Li 17 Si 4、Li 22 Si 5和Si的声子态密度、振动自由能和等容/等压比热容的热力学性质之外,还评价了如体积模量和弹性常数的机械性质。对于一个选定的相(Li_(13)Si_4),我们研究了温度依赖的声子态密度的影响及其对等压热容的影响。
First principle study of electronic, magnetic and thermoelectric properties of Co$_2$YPb (Y = Tc, Ti, Zr and Hf) full Heusler: Application to embedded automotive systems
Displacement field around a rigid sphere in a compressible elastic environment, corresponding higher-order Faxén relations, as well as higher-order displaceability and rotateability matrices