Abstract A novel laser heat treatment setup is presented and used to characterize the reverse transformation of martensite to austenite resulting from highly dynamic laser heat treatments of stainless steel. During laser heat treatments the irradiated spot and its surroundings can experience completely different thermal loads, yet both experience reverse transformation. The experiments are conducted such to reflect these diverse conditions. Next to experiments, a new kinetic model is reported which combines both athermal and isothermal transformation mechanisms to cope with the diversity in conditions in a unified framework. The experimental results show that reverse transformation can proceed extremely fast, yet saturates at intermediate temperatures. Additionally, it is shown that there is good agreement between experiment and model and it is essential to embed both the athermal and isothermal transformation mechanism in the model for achieving this performance. Initial steps towards model validation are performed showing good predictability of a non-isothermal heat treatment with conditions realistic and relevant for industrial laser heat treatments.

中文翻译：

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结合无热和等温马氏体到奥氏体的回复动力学、实验和建模

摘要 提出了一种新型激光热处理装置，用于表征不锈钢高动态激光热处理引​​起的马氏体向奥氏体的逆转变。在激光热处理过程中，照射点及其周围可能会经历完全不同的热负荷，但两者都会经历逆向转变。进行实验以反映这些不同的条件。在实验之后，报告了一种新的动力学模型，该模型结合了无热和等温转化机制，以在统一框架中应对条件的多样性。实验结果表明，逆转变可以进行得非常快，但在中间温度下会饱和。此外，结果表明，实验和模型之间有很好的一致性，必须在模型中嵌入非热和等温转变机制才能实现这种性能。模型验证的初始步骤显示了非等温热处理的良好可预测性，条件与工业激光热处理现实和相关。