Ti₂AlNb intermetallic, as a relatively new high temperature-resistant structural material, belongs to typical difficult-to-machine material due to its excellent mechanical properties. This paper aims to investigate the dynamic deformation behavior in chip shear deformation zone and associated chip formation mechanism during the machining of Ti₂AlNb intermetallic. A specialized cutting platform combined with a high speed imaging system is developed to realize in-situ detection of full field deformation and corresponding signal processing during the machining process. The high speed imaging system can capture in-situ material deformation images with a frequency of 100 kHz during cutting process while the digital image correlation method is adopted to characterize chip dynamic deformation signals quantitatively. A series of orthogonal cutting experiments for Ti₂AlNb is conducted at different cutting depths and cutting speeds, based on which the influences of cutting parameters on chip morphologies and material removal process are studied. The distribution of material flowing velocity, as well as the strain rate fields within shear deformation zone in chip removal process of Ti₂AlNb are analyzed. Finally, the formation mechanism of periodic built-up edge formed in the cutting speed range of 60–120 m·min⁻¹ is elucidated.

Ti ₂ AlNb金属间化合物作为一种较新的耐高温结构材料，由于其优异的力学性能，属于典型的难加工材料。本文旨在研究_{Ti 2 AlNb金属间化合物}加工过程中切屑剪切变形区的动态变形行为以及相关的切屑形成机制。开发了结合高速成像系统的专用切削平台，实现加工过程中全场变形的原位检测和相应的信号处理。高速成像系统可采集切削过程中频率为100 kHz的原位材料变形图像，并采用数字图像相关方法定量表征切屑动态变形信号。_{对不同切削深度和切削速度下的Ti 2 AlNb进行了}一系列正交切削实验，研究了切削参数对切屑形貌和材料去除过程的影响。分析了Ti _{2 AlNb排屑过程中}材料流速的分布以及剪切变形区内的应变率场。最后，阐明了切削速度60~120 m·min ^{-1范围内周期性积屑瘤的形成机制。}