Superimposed Dispersoid Hardening and Age Hardening of Aluminium Alloys

该项目的目标是通过叠加弥散强化和沉淀强化的新方法生产高强度铝合金。这首先需要对两种硬化机制中的温度依赖动力学和析出形成类型有基本的材料科学理解。随后，在典型的变形铝合金生产链(铸造、均化、热成形、沉淀硬化)中，工艺参数要调整到两个依赖于温度的动力学，从而产生具有潜在高强度水平的材料组织。在此基础上，讨论了工艺参数、材料结构和力学性能之间的材料科学关系，并将其具体转移到生产链中，以进一步提高强度。从我们自己的前期工作中鲜为人知的EN AW AlMn0.5Mg0.5(3105)铝合金将被研究，以了解生产链的叠加析出行为和合适的工艺参数。在另一种方法中，通过添加Zr来创造通过Al3Zr弥散球体进行弥散球体硬化的额外潜力。对于弥散球体硬化和沉淀硬化的目标叠加，将寻求潜在生产链的不同方法。这些方法是基于这样一个事实，即弥散形成的合金元素锰(和锆)在典型的退火温度下在铝中的扩散系数显著低于沉淀硬化合金元素镁和硅的扩散系数。在此基础上，目标是在过程链的第一步形成相对稳定的分散体，并在第二步形成不太稳定的沉淀物。工艺链的第二步可以在较高的温度下进行，如果工艺持续时间足够短，以抑制显著的锰扩散(和锆)。

The aim of the project is the production of high-strength aluminium alloys by the novel approach of superimposed dispersoid hardening and precipitation hardening. This initially requires a basic materials science understanding of the temperature dependent kinetics and types of precipitation formation in both hardening mechanisms. Subsequently, in a typical production chain of wrought aluminium alloys (casting, homogenising, hot forming, precipitation hardening), the process parameters are to be adjusted to the two temperature-dependent kinetics in such a way that material structures with potentially high strength levels result. Based on the results, the material-scientific correlations between process parameters, material structures and mechanical properties are to be discussed and specifically transferred to the production chain for a further increase in strength. The aluminium alloy EN AW AlMn0.5Mg0.5 (3105), which is to little extent known from our own preliminary work, will be investigated with regard to understanding the superimposed precipitation behaviour and suitable process parameters of the production chain. In a further approach, an additional potential for dispersoid hardening via Al3Zr dispersoids is to be created by adding Zr.For the targeted superposition of dispersoid hardening and precipitation hardening, different approaches of potential production chains are to be pursued. The approaches are based on the fact that the diffusion coefficient of the dispersoid-forming alloying element manganese (and Zr) in aluminium at typical annealing temperatures is significantly lower than the diffusion coefficient of the precipitation-hardening alloying elements magnesium and silicon. On this basis, the aim is to form the relatively stable dispersoids in a first step of the process chain and the less stable precipitates in a second step. The second step of the process chain can be carried out at higher temperatures if the process duration is short enough to suppress significant manganese diffusion (and Zr).