Yang Wen-Bo, Zhan Lei, Liu Lin, Meng Fan-Xu, Zhang Run, Tuerxun Kadiredan, Zhao Xing-Rui, Dong Bai-Xin, Shu Shi-Li, Liu Tian-Shu, Yang Hong-Yu, Qiu Feng, Jiang Qi-Chuan
Key Laboratory of Automobile Materials, Ministry of Education and Department of Materials Science and Engineering, Jilin University, Renmin Street No. 5988, Changchun 130025, China.
School of Automotive Engineering, Jilin Communications Polytechnic, Changchun 130012, China.
Materials (Basel). 2025 Sep 8;18(17):4206. doi: 10.3390/ma18174206.
The present study concentrates on the role and underlying mechanisms of in situ crystallization (employed for nanocrystal formation) in influencing the solidification microstructure and properties of aluminum alloys. By systematically analyzing the effects on α-Al refinement, silicon phase modification, and secondary phase control, as well as exploring the impact on room-temperature mechanical properties, high-temperature deformation behavior, and fatigue performance, this work reveals the potential physical mechanisms of improving mechanical properties by providing nucleation sites and inhibiting grain growth, such as fine-grain strengthening and dispersion strengthening. Moreover, stabilization of the second phase optimizes high-temperature deformation behavior, and a reduction in stress concentration improves fatigue performance. Compared with traditional microstructure control methods, in situ crystallization can achieve deeper grain refinement from micron to nanometer scale, ensuring high uniformity of grain distribution and showing good compatibility with existing processes. By defining the regulation of in situ crystallization on the microstructure and properties of aluminum alloy, the existing research provides a feasible material solution for high stress, high temperature, and high reliability. Its core significance lies in breaking through the performance bottlenecks of traditional modification technology, such as unstable refining effect, element segregation, and so on. The co-promotion of "strength-plasticity-stability" of aluminum alloys and the consideration of process compatibility and cost controllability lay a theoretical and technical foundation for the industrialization of high-performance aluminum alloys.
本研究聚焦于原位结晶（用于形成纳米晶体）在影响铝合金凝固组织和性能方面的作用及潜在机制。通过系统分析其对α-Al细化、硅相变质以及二次相控制的影响，并探究其对室温力学性能、高温变形行为和疲劳性能的影响，本工作揭示了通过提供形核位点和抑制晶粒生长来改善力学性能的潜在物理机制，如细晶强化和弥散强化。此外，第二相的稳定优化了高温变形行为，应力集中的降低提高了疲劳性能。与传统的组织控制方法相比，原位结晶能够实现从微米尺度到纳米尺度的更深层次晶粒细化，确保晶粒分布的高度均匀性，并与现有工艺表现出良好的兼容性。通过明确原位结晶对铝合金组织和性能的调控作用，现有研究为高应力、高温及高可靠性提供了一种可行的材料解决方案。其核心意义在于突破传统变质技术的性能瓶颈，如细化效果不稳定、元素偏析等。铝合金“强度-塑性-稳定性”的协同提升以及对工艺兼容性和成本可控性的考量，为高性能铝合金的工业化奠定了理论和技术基础。
