Mechanism-based characterization of the texture influence on the corrosion and corrosion fatigue properties of zinc-based wrought magnesium alloys

基于机制的织构对锌基变形镁合金腐蚀和腐蚀疲劳性能影响的表征

• 批准号: 461435286
• 负责人: Dr. Dietmar Letzig
• 金额: --
• 依托单位: Lehrstuhl für Werkstoffprüftechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/461435286?language=en
• 关键词: Mechanism; based; characterization; texture; influence

The proposal aims to investigate the damage mechanisms of RE- and Ca-containing extruded Mg-Zn alloys under cyclic loading in air and corrosive media. The results of previous work allow the conclusion that RE- and Ca-containing extruded Mg alloys have the potential of significantly improved properties under fatigue loading and stress corrosion cracking (SCC) conditions compared to the Al-containing Mg standard alloys. By adding suitable alloying elements and setting suitable extrusion parameters, Mg alloys with fine grain sizes and simultaneous texture weakening are to be produced, i.e. by changing the deformation mechanism, properties such as formability, increased fatigue strength, increased corrosion resistance and reduced subcritical crack propagation are to be combined. The formation of twins shall be reduced, not only by weak textures and fine grain sizes but also by homogeneous grain size distributions and suitable precipitates which reduce the formation of twins and at the same time do not hinder the slipping processes. By increasing the fatigue strength on the one hand and the corrosion resistance, on the other hand, the aim is also to achieve a significant improvement of the resistance to SCC. The different processing parameters and the resulting microstructure are to be investigated for their influence on the damage mechanisms under cyclic loading in air and under SCC conditions, and a fundamental process-microstructure-property relationship is to be derived from the findings. By correlating the course of the stress-strain hystereses with the microstructural changes, the complex interaction of the texture, the resulting anisotropy, and the tension-compression asymmetry under cyclic loading in the corrosive medium is to be characterized. The understanding of the process-microstructure-property relationships allows the development of a new group of high-performance extruded Mg alloys and the knowledge transfer to the fatigue and corrosion behavior of Mg sheet alloys in general, which forms a basis for sheet alloy development through cast rolling. Although the topic has a high scientific and economic potential, it has not been investigated yet, nor have the present damage mechanisms been researched regarding the texture influence on fatigue behavior and in particular the SCC.

该提案旨在研究在空气和腐蚀性介质中循环载荷下含有重新挤出和CA的挤压MG-ZN合金的损伤机制。先前工作的结果允许结论，与含有AL的MG标准合金相比，在疲劳负荷和应力腐蚀破裂（SCC）条件下，在疲劳负荷和应力腐蚀裂纹（SCC）条件下具有显着改善的性能的可能性。通过添加合适的合金元件并设置合适的挤出参数，将产生具有细粒尺寸和同时质地弱化的MG合金，即通过更改变形机制，外形强度，增加疲劳强度，增加腐蚀性和减少亚临界裂纹的传播。双胞胎的形成不仅应通过弱纹理和细粒度的尺寸来减少，而且还应通过均匀的晶粒尺寸分布和合适的沉淀物来减少，从而减少双胞胎的形成，同时也不会阻碍滑动过程。另一方面，通过增加疲劳强度，另一方面，耐腐蚀性也是为了显着提高SCC的抗性。应研究不同的处理参数和所得的微观结构，因为它们对空气和SCC条件下循环载荷下的损伤机制的影响以及基本过程 - 微观结构 - 培训关系将从这些发现中得出。通过将应力 - 应变膜的过程与微观结构变化，质地的复杂相互作用，所得各向异性的复杂相互作用以及在腐蚀介质中环状载荷下的张力压缩不对称性相关联。对过程 - 微观结构 - 特性关系的理解允许开发一组新的高性能挤出型毫克合金，并将知识转移到MG纸合金的疲劳和腐蚀行为上，这通常是通过铸造滚动滚动的合金开发的基础。尽管该主题具有很高的科学和经济潜力，但尚未对其进行研究，也没有研究有关质地对疲劳行为的影响，尤其是SCC的纹理影响。