The experimental results show that the oil mist is the better cutting fluid compared with dry cutting and jet cold air, producing not only the smallest specific cutting force but also the smallest surface roughness and dimensional error. Therefore, oil mist is beneficial to micromilling of thin walls made of the Ti-6Al-4V titanium alloy by polycrystalline diamond end mills.

A special deformation prediction model for titanium alloy in thin wall machining is established and calibrated by micromilling experiments. The model has been successfully evaluated by micromilling experiments. It shows that the dimensional errors of the thin wall made of Ti-6Al-4V are significantly reduced after on-machine radial cutting depth compensations. The relative errors have been reduced from 16.5 % to 3.9 %.