Micro-Scale Characterization of Machining Interfaces

加工界面代表了重要的现象事件在小空间和短时间尺度上发生的情况。通过将各种光学技术与透明切割工具的使用相结合；例如，蓝宝石、钻石，可以通过放大它们的长度和时间尺度来直接观察和分析这些事件。视觉记录经常为正在发生的物理过程提供线索，并且在显示“发生了什么和没有发生什么”方面通常是有利的。通过一系列新的实验，研究工具-芯片-工作界面的接触性质，以及这些接触区域的温度分布，这些实验将使用光学透明工具、高分辨率光学显微镜、高速、基于ccd的多波长红外（IR）高温法和高速显微摄影。初步观察表明，使用这些技术可以获得接触边界条件的完整表征（例如粘着程度，滑动区等）以及这些界面上完整的温度和速度分布的第一张详细地图。研究了常规和高速切削工况下的切削速度、刀具几何形状、刀具磨损和刀具涂层等参数对接触条件和界面温度的影响。这些实验代表了以往金属低速切削现场观测工作的自然而有趣的发展。接触边界条件和界面温度分布是验证和完善加工力学模型的关键参数；用于控制刀具温度、刀具磨损和工件表面质量；实现了机械加工过程的完全可预测性这一长期追求的目标。从技术的角度来看，研究结果可能会对提高加工过程的效率产生重大影响，使设计工具和涂层能够减少磨损并减少加工中流体的应用。

The machining interface represents a situation where important phenomenological events occur over small spatial and short time scales. By combining various optical techniques with the use of transparent cutting tools; e.g., sapphire, diamond, it is possible to directly observe and analyze these events by magnifying their length and time scales. Having a visual record frequently gives clues to the physical processes taking place and is often advantageous in showing "what is and what isn't happening." The nature of contact along the tool-chip-work interfaces, and the temperature distribution at these contact zones, will be studied in a novel series of experiments using optically transparent tools, high-resolution optical microscopy, high-speed, CCD-based, multi-wavelength infra-red (IR) pyrometry and high-speed micro-photography. Preliminary observations show that a complete characterization of the contact boundary conditions (e.g. extent of sticking, sliding zones, etc.) and the first detailed map of the complete temperature and velocity distributions at these interfaces can be achieved with the use of these techniques. The effect of parameters such as cutting speed both in the conventional and high speed machining regime, tool geometry, tool wear, and tool coatings, on the contact conditions and interface temperatures is being explored. The experiments represent a natural and interesting evolution of previous in-situ observational work on the low speed cutting of metals. The contact boundary conditions and the interface temperature distributions are key parameters for validation and refinement of models of the mechanics of machining; for control of tool temperatures, tool wear and work surface quality; and for realizing the long sought after goal of complete predictability of the machining process.From a technological standpoint, the results of the research may be expected to have a major impact in enhancing the efficiency of machining processes, enabling the design of tools and coatings for reducing wear and reducing the application of fluids in machining.