Microstructure and Thermophysical Properties of Mg-Ga Alloys

【摘要】 The microstructure and thermal characteristics of Mg-36%Ga,Mg-43%Ga,and Mg-45%Ga（wt%） alloys were investigated.The experimental results show that the microstructure of Mg-36%Ga alloy is mainly composed of primary a-Mg phase and a-Mg+Mg₅Ga₂ eutectic phase,the microstructure of Mg-43%Ga alloy is mainly composed of a-Mg+Mg₅Ga₂ eutectic phase,and the microstructure of Mg-45%Ga alloy is mainly composed of primary Mg₅Ga₂ phase and a-Mg+Mg₅Ga₂ eutectic phase.The melting enthalpies of Mg-36%Ga,Mg-43%Ga,and Mg-45%Ga are 146.41,171.90,and 113.90 J/g,with the phase change temperature of 422.57,422.70,and 422.90 ℃,respectively.Mg-43%Ga alloy contains the highest melting enthalpy because of the highest content of a-Mg+Mg₅Ga₂ eutectic phase.In addition,the thermal expansion of the three alloys increases with increasing temperature,while the thermal diffusivity and thermal conductivity decreases with increasing content of Ga.更多还原

【Abstract】 The microstructure and thermal characteristics of Mg-36%Ga,Mg-43%Ga,and Mg-45%Ga（wt%） alloys were investigated.The experimental results show that the microstructure of Mg-36%Ga alloy is mainly composed of primary a-Mg phase and a-Mg+Mg₅Ga₂ eutectic phase,the microstructure of Mg-43%Ga alloy is mainly composed of a-Mg+Mg₅Ga₂ eutectic phase,and the microstructure of Mg-45%Ga alloy is mainly composed of primary Mg₅Ga₂ phase and a-Mg+Mg₅Ga₂ eutectic phase.The melting enthalpies of Mg-36%Ga,Mg-43%Ga,and Mg-45%Ga are 146.41,171.90,and 113.90 J/g,with the phase change temperature of 422.57,422.70,and 422.90 ℃,respectively.Mg-43%Ga alloy contains the highest melting enthalpy because of the highest content of a-Mg+Mg₅Ga₂ eutectic phase.In addition,the thermal expansion of the three alloys increases with increasing temperature,while the thermal diffusivity and thermal conductivity decreases with increasing content of Ga.更多还原