Plasticity enhancement by engineered defect's architecture and concurrent electron-transport properties in Mg-based alloys.

所提出的研究的广泛目标是发展对纯Mg和选定Mg合金塑性变形过程中产生的晶格缺陷的性质的基本理解，以及这些缺陷对机械和电子输运性质的影响。这些知识对于设计和制造具有优异性能的低成本镁合金的创新解决方案是必要的，适用于不同的应用。该计划的目标是针对Mg和Mg合金中结构-性能关系的各个方面，这些方面需要很好的理解，但以前从未研究过或没有得到充分的解决。这些包括：(i)了解晶格缺陷的结构和性质，这些缺陷是在孪晶过程中由变形孪晶继承的，以及各种晶格缺陷被纳入孪晶晶格的机制。该研究将有助于了解变形孪晶在塑性和断裂中的作用，以及孪晶对Mg和镁合金物理性能的影响。（ii）了解指导制造工艺设计的原则，以开发优化的缺陷结构，从而提供强度和延展性的卓越组合。（iii）了解晶格缺陷和溶质原子存在下的电子输运，外加磁场对电子输运的影响以及宏观流动应力与电导率之间的关系。本文将采用实验方法和理论研究相结合的方法来达到研究目的。该研究将有助于更好地了解晶体缺陷的原子结构和性质，缺陷存在时电子传输的性质，以及它们对镁合金功能特性的影响。该程序强调了变形孪晶与机械和电磁性能之间的联系，因为这些知识是缺失的，但它对于设计合金成分和实现合金优越功能性能的加工路径至关重要。上述前两个目标的进展将为飞机和航天工业、军用航空系统、直升机和汽车工业中具有优越机械性能的镁合金的开发和微观结构设计提供指导。了解晶格缺陷下的电子传输将有助于指导民用航空和军事空间系统中电子工业中镁基材料的发展，这些系统需要轻质，坚固和耐用的材料来屏蔽电磁干扰和辐射防护。在计划过程中开发的基础知识可转移到其他HCP工程合金中。

The broad aim of the proposed research is to develop a fundamental understanding of the properties of lattice defects produced during plastic deformation of pure Mg and selected Mg-alloys and the influence of these defects on mechanical and the electron-transport properties. This knowledge is necessary to develop innovative solutions in the design and fabrication of low-cost Mg-alloys with superior properties for different applications. The objectives of the proposed program target the aspects of the structure-property relationship in Mg and Mg alloys that demand a good understanding, but have never been studied before or have been addressed insufficiently. These include: (i) understanding the structure and properties of lattice defects, which are inherited by deformation twins form the parent during the twinning process and the mechanisms by which various lattice defects are incorporated into the twin lattice. The study will permit to understand the role of deformation twins in plasticity and fracture and the effect of twins on the physical properties of Mg and Mg alloys. (ii) understanding the principles that would guide the design of the fabrication process for the development of the optimized defect architecture, which delivers a superior combination of strength and ductility.(iii) understanding the electron-transport in the presence of lattice defects and solute atoms, the influence of applied magnetic field on the electron-transport and the relationship between macroscopic flow stress and electrical conductivity.The objectives will be achieved by employing experimental methods and theoretical studies. The research will allow gaining a better fundamental understanding of the atomic structure and properties of crystal defects, the nature of the electron transport in the presence of defects, and their influence on functional properties of Mg alloys. The program highlights the link between deformation twinning and the mechanical and galvanomagnetic properties because this knowledge is missing, but it is crucial in designing alloy composition and the processing path for achieving superior functional properties of the alloys. The progress in first two objectives above will provide guidance for the development and microstructural design of Mg alloys with superior mechanical properties for applications in aircraft and space industry, military air systems, helicopters and automotive industry. The understanding of electron transport in the presence of lattice defects will help to guide the development of Mg-based materials for the electronic industry in civil air and military space systems, where the lightweight, strong and durable materials are required for electromagnetic interference shielding and radiation protection. The fundamental knowledge that will be developed during the course of the proposed program is transferable onto other HCP engineering alloys.