高铁含量铸造铝合金热/力耦合作用下的微观组织演变与导热机理

开发高铁含量的高性能铸造铝合金对促进再生铝高效利用有着非常积极的作用。目前针对高铁含量铸造铝合金主要侧重于强韧化及其机理的分析，缺乏对这类合金导热性能和导热机理的深入研究。本项目以较高铁含量（Fe≥0.5%）的铸造Al-Si系和Al-Cu系合金为对象，研究合金在以高压（0.2-1.0GPa）、不同快冷（普通金属模、水冷铜模和液体淬火）、高能超声为主要特征的热/力耦合作用下的微观组织演变和导热机理。创新之处是明晰热/力耦合作用下微观组织演变对高铁含量铝合金导热性能的影响及其机理，揭示基于高压快冷、高压超声复合为主要特征的热/力耦合作用下不同形貌富铁相的形核和生长机制，为开发新型高压铸造成形工艺提供技术原型。本项目研究将为提升高铁含量铸造铝合金综合性能提供理论指导，促进再生铝的高效利用，同时丰富铝合金特种铸造条件下的凝固理论。

The development of high performance cast aluminum alloys with high iron contents is benefit to the utilization of aluminum scrap efficiently. So far, the main concern is focus on the strengthening and toughening mechanism of the iron-rich cast aluminum alloys and there is little concern on the thermal property and thermal conductivity mechanism. In this proposal, the microstructure evolution and thermal conductivity mechanism of Al-Si based and Al-Cu based alloys with high iron contents (more than 0.5%) will be investigated by high applied pressure (0.2-1.0 GPa), rapid cooling ( such as permanent mold cooling, coper mold with water cooling or liquid quench cooling) and ultrasonic processing. The novelty is revealing the effect of thermal-mechanical process on thermal property, the thermal conductivity mechanism and the nucleation and growth mechanism of iron-rich phases during thermal-mechanical process by combining high applied pressure and rapid cooling or high applied pressure and ultrasonic treatment. Another novelty lies in offering a technical porotype for casting technology combined high pressure and rapid cooling. The results in the project are helpful for the development of novel high performance cast aluminum alloys with high iron contents and the promotion of high efficient utilization of recycling aluminum. It is also available for the development of solidification theory.