Quenching and Deformation Dilatometer

淬火变形膨胀仪可在不同的工作模式下使用。在淬火模式下，以高达1000 K/s的加热速率对金属样品进行快速感应加热，加热温度可达约。1500°C，随后通过气体喷嘴阵列快速淬火，冷却速度可达1000 K/s。同时，测量样品的长度变化。这使得几乎任何金属材料热处理过程中的相变（与足够的体积变化相关）都可以在现场监测。在变形模式下（压缩或拉伸），这些几乎任意的热处理可以在任何时候停止，以便通过其流动曲线来表征材料在当前温度下的状态，甚至远离平衡（热力分析）。用这种方法对金属样品进行热机械处理，然后可以研究其纳米级材料结构，并通过量热法作为进一步热分析的初始状态。激光超声检测是一种结合膨胀测量法进行材料结构原位分析的新方法。在这里，用短激光脉冲轰击样品表面，从而触发样品内部的超声波。检测超声波对相反样品表面的影响。超声波的特性，如声速和衰减，可以与材料结构的特性相关联。有了这种设备，所提出的设备有一个独特的卖点，它为申请人在现场分析相变开辟了全新的可能性，这与非常小的体积变化有关。因此，淬火和变形膨胀仪是罗斯托克大学材料科学主席不可缺少的研究设备，其研究重点是金属材料，热处理工艺/设备，热处理模拟和材料数据/材料模型模拟。热处理工艺还包括本质上与热处理相结合的制造工艺（例如铸造、增材制造、热成型、连接）。目前使用该研究设备的研究项目包括铝合金的沉淀硬化、铝合金的双辊铸造、钢的感应硬化、Ni-Ti合金的感应热处理和Cu合金的增材制造。计划的研究项目包括铝合金的增材制造、增材制造钢的表面硬化、铝合金的叠加人工时效和蠕变以及高熵合金的烧结。

The quenching and deformation dilatometer can be used in different operating modes. In the quenching mode, rapid inductive heating of metallic samples with heating rates of up to several 1000 K/s to temperatures of up to approx. 1500 °C and subsequent rapid quenching by means of a gas nozzle array with cooling rates of up to several 1000 K/s is possible. In parallel, the length change of the sample is measured. This allows the phase transformations during almost any heat treatment of metallic materials (which are associated with a sufficient volume change) to be monitored in-situ. In the deformation mode (compression or tension), these almost arbitrary heat treatments can be stopped at any time in order to characterise the material state present at the current temperature by its flow curve, even far from equilibrium (thermomechanical analysis). Metallic samples treated thermomechanically in this way can then be investigated with regard to their nanoscale material structure and serve as initial states for further thermal analyses by means of calorimetry.A new method integrated into dilatometry for the in-situ analysis of material structures is laser ultrasonic testing. Here, a sample surface is bombarded with a short laser pulse, which triggers an ultrasound wave inside the sample. The impact of this ultrasonic wave on the opposite sample surface is detected. Characteristics of the ultrasonic wave, such as the speed of sound and the attenuation, can be correlated with characteristics of the material structure. With this equipment, the proposed device has a unique selling point, which opens up completely new possibilities for the applicant to analyse phase transformations in-situ, which are associated with very small volume changes.The quenching and deformation dilatometer is thus an indispensable research device for the Chair of Materials Science at the University of Rostock with its research focus on metallic materials, heat treatment processes/equipment, heat treatment simulations and material data/material models for simulations. Heat treatment processes also include manufacturing processes that are intrinsically combined with heat treatment (e.g. casting, additive manufacturing, hot forming, joining). Current research projects in which the research equipment is to be used include precipitation hardening of Al alloys, twin-roll-casting of Al alloys, induction hardening of steels, inductive heat treatment of Ni-Ti alloys and additive manufacturing of Cu alloys. Planned research projects include additive manufacturing of Al alloys, case hardening of additively manufactured steels, superimposed artificial ageing and creep of Al alloys and sintering of high entropy alloys.