钛铝合金具有密度小、强度高、抗高温蠕变与抗氧化能力强等优势，在航天航空工业的应用前景广阔。但由于材料导热性能差、加工硬化严重、低温脆性，在切削加工中切削温度高，导致切削加工效率低、刀具寿命低和表面完整性差，限制了材料的应用推广。针对钛铝合金切削温度高的问题，基于其力学性能对温度敏感的特性，在钛铝合金Ti-48Al-2Cr-2Nb材料力学性能、材料去除机理和切削加工表面完整性等方面开展了研究工作。通过霍普金森冲击剪切试验研究了材料在不同温度下的动态失效行为和断裂机理；通过有限元仿真和试验研究了不同冷却条件和切削参数下直角车削的切屑形貌及其形态演化，分析了材料去除机理；对材料进行了3种冷却条件下的端面车削试验，分析了表面粗糙度的变化规律；结合材料的断裂机理和片层组织断裂形式，揭示了微凹坑与微裂纹等表面缺陷的形成原因；结合切削力与切削温度分析了加工硬化程度与硬化层深度，揭示了硬度的变化原因。

Titanium aluminum alloy has such advantages as low density， high strength， good high-temperature creep resistance and oxidation resistance， and has broad application prospects in the aerospace industry. However， due to the poor thermal conductivity， severe work hardening， and low-temperature brittleness of the material， the high cutting temperature during the cutting processing leads to low machining efficiency， low tool life， and poor surface integrity， which limits the application promotion of this material. this paper Focusing on the problem of high cutting temperature of titanium aluminum alloy， and based on its temperature sensitive mechanical properties， this paper investigates the mechanical properties， material removal mechanism， and surface integrity of titanium aluminum alloy Ti-48Al-2Cr-2Nb material. The dynamic failure behavior and fracture mechanism of the material at different temperatures are studied through Hopkinson impact shear tests. The chip morphology and morphology evolution under different cooling conditions and cutting parameters are simulated through finite element simulation. Face turning experiments are conducted under three different cooling environments， and the changing rule of surface roughness is analyzed. Combining the fracture mechanism of the material and the fracture form of the lamellar structure， the formation mechanisms of micro pits and microcracks are revealed. The degree of work hardening and the depth of the hardened layer are analyzed by combining cutting force and cutting temperature， revealing the changing rule of hardness.