To obtain the aluminum alloy with high thermal and mechanical properties, the effects of alloying elements and the second phases on the thermal conductivity of Al alloys were investigated by CALPHAD and first-principles calculation, respectively. The properties of the second phases, including Young’s modulus, Poisson’s ratio and minimum thermal conductivity, were systematically studied. Results show that the ranking order of the effects of the alloying elements on the thermal conductivity is Mg>Cu>Fe>Si, and for Al-12Si alloys, the mathematical model of the relationship between the alloying elements and the thermal conductivity can be expressed as λ=ax²-bx+c when the second phase precipitates in the matrix. All kinds of ternary phases of Al-Fe-Si have higher deformation resistance, rigidity, theoretical hardness, Debye temperature and thermal conductivity than the other phases which possibly exist in the Al-12Si alloys. Based on the guidance of CALPHAD and first-principles calculation, the optimized chemical composition of Al alloy with high conductivity is Al-11.5Si-0.4Fe-0.2Mg (wt.%) with a thermal conductivity of 137.50 W·m⁻¹·K⁻¹ and a hardness of 81.3 HBW.

为了获得具有高热力学和力学性能的铝合金，分别通过CALPHAD和第一性原理计算研究了合金元素和第二相对铝合金热导率的影响。系统研究了第二相的杨氏模量、泊松比和最小热导率等性质。结果表明，合金元素对热导率的影响排序为Mg>Cu>Fe>Si，对于Al-12Si合金，合金元素与热导率关系的数学模型可以表示为λ = ax ² - bx + c _当第二相在基体中析出时。与Al-12Si合金中可能存在的其他相相比，Al-Fe-Si的各种三元相具有更高的变形抗力、刚度、理论硬度、德拜温度和热导率。基于CALPHAD和第一性原理计算的指导，优化后的高导铝合金化学成分为Al-11.5Si-0.4Fe-0.2Mg（wt.%），热导率为137.50 W·m ^-1 · K ^-1和 81.3 HBW 的硬度。