Manufacturing of tailored aluminum parts by controlling the local cooling rates in a combined forming, quenching and hardening process (Tailor Quenched Forming)

提高车辆乘客安全性的一种常见方法是在与结构安全相关的部件上使用高强度材料。由于机械性能的有针对性的调整，定制的部件可以用本地适应的部件强度来制造。在发生碰撞的情况下，他们有能力吸收或转移发生的能量到车辆的其他区域。相关的是，这些部件结合了高强度和延展性区域。到目前为止，这些部件只能通过改进的钢部件的冲压硬化操作来生产。与轻量化概念相联系，实现定制部件的新机会是使用经过调整的高强度、可淬火的铝部件。在成形过程中，可以通过同时进行淬火和成形操作来调整先前固溶退火部件的性能。在淬火和成形操作中，关键影响因素是冷却速度。在未来，在不同的局部工具温度的帮助下，使用高强度铝合金来生产与性能相适应的结构部件是可能的。热耦合材料模型是模拟该成形过程所必需的。因此，本项目的目的首先是确定高强铝合金的微观组织行为作为冷却速度和机械应力状态的函数。然后，确定的材料属性将被转移到热力耦合材料模型中，并将得到降水模拟。这使得可以将同时成形和淬火操作转移到有限元模拟中。通过实验研究了刀具与零件间换热的影响因素。此外，还研究了工具内部硬化与炉内常规淬火的可能性。使用简化的演示器几何形状验证了结果。

A common method for increasing passenger safety in vehicles is the use of high strength materials for structural safety-relevant parts. Due to the targeted adjustment of the mechanical properties, tailored components can be manufactured with locally adapted component strengths. In case of a crash, they have the ability to absorb or transfer the occurring energy to other regions of the vehicle. It is relevant that these components combine high-strength as well as ductile regions. Until now these components are only produced by modified press hardening operations of steel components. In association with the light-weight concept, a new opportunity to realize tailored components is the use of adapted, high-strength, hardenable aluminum components. During the forming process, the properties of previously solution-annealed components can be adjusted by simultaneous quenching and forming operations. The key influencing factor in quenching and forming operations is the cooling rate. In future, it will be possible to produce property-adapted structural components using high-strength aluminum alloys with the help of different local tool temperatures. Thermally coupled material models are necessary for the simulation of this forming process. Aim of this project is therefore at first the determination of the microstructural behavior of high-strength aluminum alloys as a function of cooling rate as well as mechanical stress states. The determined material properties will then transferred into a thermomechanically coupled material model and a precipitation simulation will be derived. This enables the transfer of the simultaneous forming and quenching operation into a FEM simulation. The influencing variables of the heat transfer between tool and component are investigated by experiments. Furthermore, the possibility of tool-internal hardening in comparison to conventional hardening in a furnace is investigated. The results are verified using a simplified demonstrator geometry.