Surface integrity is directly related to component performance and service life. Various characteristics of the surface integrity of the three typical γ-TiAl alloys by electrochemical machining (ECM) were studied, including surface morphology, 3D profile, surface roughness, cross section, microhardness, residual stress and element analysis. Two current densities 5 and 50 A/cm² were selected for comparative experiments. The results show that the three γ-TiAl alloys exhibit their own unique morphologies at low current density, and there is severe localized corrosion on the machined surface, resulting in the rough surface. However, the three γ-TiAl alloys show very smooth surfaces at high current density. This result also shows that the surface roughness values of the three γ-TiAl alloys all decrease gradually with the current density increasing, in which the extruded Ti-48Al-2Cr-2Nb has lowest surface roughness value (about Ra 0.506 μm) at 50 A/cm². It is found that the microhardness of the machined surface of the three γ-TiAl alloys all decreased slightly, with a decrease of about 10 HV compared with the matrix. The residual stress of the samples decreases slightly after ECM, and the influence of different current density on the residual stress is not obvious. Finally, it is also proved that ECM has no effect on the elements of the machined surface.

表面完整性直接关系到组件的性能和使用寿命。研究了三种典型的γ-TiAl合金通过电化学加工（ECM）的表面完整性的各种特征，包括表面形态，3D轮廓，表面粗糙度，横截面，显微硬度，残余应力和元素分析。两种电流密度5和50 A / cm ²选择用于比较实验。结果表明，三种γ-TiAl合金在低电流密度下表现出独特的形貌，并且在加工表面上存在严重的局部腐蚀，从而导致表面粗糙。但是，三种γ-TiAl合金在高电流密度下均显示出非常光滑的表面。该结果还表明，三种γ-TiAl合金的表面粗糙度值均随电流密度的增加而逐渐减小，其中挤出的Ti-48Al-2Cr-2Nb在50 A时具有最低的表面粗糙度值（约Ra 0.506μm）。 /厘米²。发现三种γ-TiAl合金加工表面的显微硬度均略有降低，与基体相比降低了约10 HV。ECM后样品的残余应力略有降低，不同电流密度对残余应力的影响不明显。最后，还证明了ECM对加工表面的元素没有影响。