Ionic Liquids as Quenching Media for Heat Treatment of Metals

在第一个项目期间，我们已经证明，铝合金可以成功地在离子液体中淬火。在离子液体中淬火会导致快速而均匀的冷却过程。在不引起宏观膜沸腾的情况下，加水可提高淬火速率。此外，我们已经证明，离子液体在快速加热时蒸发而不是分解。在离子液体猝灭机理、离子液体猝灭剂的选择和应用方面，将继续开展这一成功的工作。以前的高分解温度的主要选择标准已不再有效。因此，可能合适的离子液体的范围显著增加。例如，无卤素离子液体可能适合，在腐蚀和工作安全方面具有优势。此外，在离子液体中进行了第一次有希望的钢的淬火试验（退火温度高于800°C）。对这一新应用应进行详细研究。减少残余应力和变形的巨大潜力应研究使用更复杂和变形敏感的部件几何形状。最后，应改进热重测量，以确定离子液体的沸腾温度取决于压力。

In the first project period, we have shown, that aluminium alloys can successfully be quenched in ionic liquids. Quenching in ionic liquids results in a rapid, but also homogeneous cooling process. The quenching rate can be increased by the addition of water, without inducing macroscopic film boiling. Further, we have shown, that ionic liquids evaporate rather than decompose during fast heating. This successful work shall be continued in four combined directions, to proceed regarding mechanisms of ionic liquid quenching, as well as selection and application of ionic liquid quenchants. The former main selection criterion of a high decomposition temperature is no longer valid. Thereby, the range of possibly suitable ionic liquids increases significantly. E.g. halogen free ionic liquids may be suitable with advantages regarding corrosion and work safety. Further, first promising quenching test of steels (annealing temperature above 800°C) have been performed in ionic liquids. This new application shall be investigated in detail. The huge potential for reducing residual stresses and distortion shall be investigated using more complex and distortion sensitive component geometries. Finally, thermogravimetric measurements shall be improved, to determine boiling temperatures of ionic liquids depending on pressure.