High Strength Wrought Aluminium Alloys from the Casting Heat

该项目的目的是研究制造参数、微观结构和性能之间的材料科学关系，以用于生产挤压高强度变形铝合金的新工艺链。这种新颖的工艺链应导致在必要的能量输入相当大的减少，通过连续使用铸造热。省去了铸造、均质退火、热成形、固溶退火等工序高温之间的多次冷却、再加热。工作假设是，如果在相图证明的温度范围内进行均质化、热成形和溶液退火，即低于分散成形合金元素（例如Mn， Fe）的溶剂温度和高于沉淀硬化合金元素（例如Mg， Si）的溶剂温度，则可以通过有目的地选择合金和工艺参数，从铸造热中生产高强度变形铝合金。在这个过程窗口中，分散体应该已经形成，以阻碍晶粒长大，但析出硬化合金元素仍然保持溶解，以便在淬火后设置较高的时效势。这似乎是有目的的，因为弥散形成的合金元素（如Mn， Fe）在铝固溶体中的温度溶解度通常低于沉淀硬化合金元素（如Mg， Si）。

The aim of the project is to research the material science relationships between manufacturing parameters, microstructures and properties for a novel process chain for the production of extruded high-strength wrought aluminium alloys. This novel process chain should lead to a considerable reduction in the necessary energy input through the continuous use of the casting heat. The multiple cooling and reheating between the high process temperatures of casting, homogenisation annealing, hot forming and solution annealing shall be saved. The working hypothesis is that high-strength wrought aluminium alloys can be produced from the casting heat through the purposeful selection of alloys and process parameters if homogenisation, hot forming and solution annealing are carried out in a temperature range justified by phase diagrams, i.e. below the solvus temperature of dispersoid-forming alloying elements (e.g. Mn, Fe) and above the solvus temperature of precipitation-hardening alloying elements (e.g. Mg, Si). In this process window, dispersoids should already be formed in order to hinder grain growth, but the precipitation-hardening alloying elements should still remain dissolved in order to set a high ageing potential after quenching. This seems to be purposeful because the dispersoid-forming alloying elements (e.g. Mn, Fe) usually have lower temperature-specific solubilities in the aluminium solid solution than precipitation-hardening alloying elements (e.g. Mg, Si).