Laser-Induced Plasma Micro-Machining (LIP-MM)

该研究项目的目标是一种新的微制造工艺的概念，该工艺模拟了表征微电火花加工的材料去除机制。它不需要使用电极，也不局限于导电材料。该工艺将使用超短激光脉冲聚焦在略高于工件表面的电介质上，而不是电极和导电工件之间的放电，以产生等离子体，其爆炸性膨胀有助于材料的去除。这项工作将涉及一个实质性的实验组成部分，重点是该过程的物理实现。此外，过程表征将通过使用嵌入式微型传感器来测量等离子体产生的冲击波源下方的温度和应力。理论工作将集中在等离子体特性的建模和控制，以及控制激光诱导等离子体辅助过程的物理原理的研究，重点是等离子体-物质相互作用和材料去除机制。新工艺将提供其他现有竞争方法无法实现的独特能力，用于制造微尺度部件，并具有高精度和复杂几何形状的特点，适用于各种工程材料。它还将完全避免与刀具制造、微电火花加工中的磨损和补偿以及传统激光加工的复杂性相关的问题和成本。通过使用嵌入式微传感器对新开发的工艺进行实时过程监控，将提供前所未有的对加工过程中材料的热和机械响应的即时洞察。这种监控技术一旦成功实现，也将适用于其他微观和宏观尺度的过程监控任务。

The objective of this research project is the conception of a new micromanufacturing process that emulates the material removal mechanisms that characterize micro electro-discharge machining. It will not require the use of electrodes and will not be limited to conductive materials only. The process will use ultra-short laser pulses focused in a dielectric slightly above the workpiece surface - instead of electric discharges between an electrode and a conductive workpiece - to create plasma whose explosive expansion facilitates material removal. The work will involve a substantial experimental component focused on the physical realization of the process. In addition, process characterization will be performed through the use of embedded micro-sensors to measure the temperature and stresses just below the source of the shock waves created by the plasma. The theoretical work will focus on the modeling and control of plasma properties and on the investigation of the physical principles that govern the laser-induced plasma-assisted process with emphasis on plasma-matter interaction and the material removal mechanisms. The new processes will offer unique capabilities not achievable by other currently existing competing methods for the manufacture of micro-scale components and features with high relative accuracy and complex geometries in a wide range of engineering materials. It will also entirely circumvent problems and costs associated with tool manufacture, wear and compensation in micro electro-discharge machining and the complexities of conventional laser processing. Real time process monitoring of the newly developed process through the use of embedded micro-sensors will offer an unprecedented instantaneous insight into the thermal and mechanical responses of the material during processing. This monitoring technique, once successfully realized, will also be applicable to other micro- as well as macro-scale process monitoring tasks.