论文标题
金属粉末的微波闪光烧结：从实验证据到多物理模拟
Microwave flash sintering of metal powders: From experimental evidence to multiphysics simulation
论文作者
论文摘要
闪光烧结现象主要与陶瓷相关，这是由于其电导率的热逃亡者在氧化锆或碳化硅等材料中明显表示。由于其高电导率，金属的闪光烧结几乎没有存在。在这项工作中，提出了一种基于微波炉方法的原始金属粉末闪光烧结方法。在开发的方法中，在微波照明下揭示了TI-6AL-4V粉末的异常快速（60 s）热和烧结的失控。该现象是基于电磁热机械（EMTM）模型模拟的。开发的多物理模型表明，金属粉末标本的失控不是由其内在材料特性引起的，而是由周围工具材料热激活的共振现象引起的。 EMTM模拟以非常良好的精度预测微波炉的重新分配以及产生的致密性和粉末标本的形状扭曲，从而实验观察到。微波和常规烧结动力学的比较表明，在微波加热下烧结行为的重要加速度。开发的烧结方法具有实施的潜力，用于实施小金属零件的时间生产。
Flash sintering phenomena are predominantly associated with ceramics due to thermal runaway of their electric conductivity noticeably represented in materials such as zirconia or silicon carbide. Because of their high electric conductivity, flash sintering of metals is nearly inexistent. In this work, an original metal powder flash sintering method based on a microwave approach is presented. Within the developed approach, an unusually fast (60 s) thermal and sintering runaway of Ti-6Al-4V powder is experimentally revealed under microwave illumination. This phenomenon is simulated based on an electromagnetic-thermal-mechanical (EMTM) model. The developed multiphysics model reveals that the metal powder specimen's runaway does not result from its intrinsic material properties, but results from the resonance phenomenon thermally activated by the surrounding tooling material. The EMTM simulation predicts with a very good accuracy the microwave repartition and the resulting densification and powder specimen's shape distortions observed experimentally. The comparison of the microwave and conventional sintering kinetics indicates an important acceleration of the sintering behavior under microwave heating. The developed sintering approach has a potential of the implementation for time-effective mass production of small metal parts.
