First-principles investigation of intermetallic compounds of Mg-Al-Sr alloy: thermal stability, electronic and elastic properties
The structural, electronic and elastic properties of intermetallic compounds of Mg-Al-Sr alloy, such as Mg17Al12, Al2Sr, Al4Sr, Mg2Sr, MgSr and Mg17Sr2, are investigated by using first-principles technique. The calculation results of heat of formation and cohesive energy show that the Al2Sr phase is of the strongest alloying ability and structural stability. The calculations of thermodynamic properties indicate that the Gibbs free energy of these compounds change with the elevated temperature, when the temperature is within 325-425K range, Al2Sr and Mg17Sr2 are more stable than Mg17Al12 phases and Sr addition to the Mg-Al-based alloys can improve the heat resistance. The densities of states (DOS) of these compounds are given. The elastic parameters are calculated, then the bulk modulus, shear modulus, Young s modulus and poisson ratio value are derived. All the results of the analysis indicate that adding Sr to Mg-Al alloy can improve the ductility and plasticity.
D.W.Zhou J.S.Liu S.H.Xu P.Peng
State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082
国际会议
武汉
英文
291-306
2010-09-01（万方平台首次上网日期，不代表论文的发表时间）