Tool deflection is severe in the micro milling process with flexible tools. Existing models usually predicted the machining errors caused by tool deflection through time-consuming iteration algorithms. This article presents an efficient method to predict the machining errors caused by tool deflection in the side-wall milling process. The concept of equivalent modulus is proposed to describe the tool deflection behavior under cutting loads. It is found that the radial cutting force at the immersion angle of π is the actual cause of the machining errors. To describe the influence of instantaneous actual cutting direction shifts in the down milling process with flexible tools, the cutter is regarded as pressing into the workpiece during the cutting process, and the total cutting load is regarded as the combination of cutting forces and the press force. The material piling up and strain hardening is included in this model. Verifications show that the proposed model can greatly save the computational time without losing prediction accuracy.

Milling is widely used to machine the structures with low-rigidity in the astronautic and aeronautic industries, while chatter vibration, which is a great limitation and a serious problem, occurs easily in this kind of process due to the weak stiffness of the structures. To solve the machining problems caused by chatter, prediction and suppression are two important methods that are commonly used by researchers and industry engineers. This article reviews the study progresses on the prediction and suppression of the chatter occurring in milling process of the low-rigidity structure. The dynamic model, acquisition of dynamic parameters, and suppression techniques are introduced. Besides, the problems and the outlooks of the future coming research topics are also given in the conclusions.