Study on Machining Deformation of Aircraft Monolithic Component by FEM and Experiment

Machining deformation of aircraft monolithic component is simulated by finite element method （FEM） and validated by experiment. The initial residual stress in pre-stretched plate is generated by simulating quenching and stretching processes. With a single tool-tooth milling process FEM, the machining loads in monolithic component material removing is obtained. Restart-calculation is put forward to complete the whole simulation of machining process. To verify the FEM result, an experiment is carried out. The deformation distribution of the monolithic component resulting from FEM shows a good agreement with the experiment result, which indicates that the key technologies presented in the paper are practicable and can be used to simulate the milling process of monolithic component to predict its deformation. Lengthy and expensive trial and error experiment process can be avoided.

Machining distortion prediction of aerospace monolithic components

To predict the distortion of aerospace monolithic components, a model is established to simulate the numerical control (NC) milling process using 3D finite element method (FEM). In this model, the cutting layer is simplified firstly. Then, the models of cutting force and cutting temperature are established to gain the cutting loads, which are applied to the mesh model of the part. Finally, a prototype of machining simulation environment is developed to simulate the milling process of a spar. Key factors influencing the distortion, such as initial residual stress, cutting loads, fixture layout, cutting sequence, and tool path are considered all together. The total distortion of the spar is predicted and an experiment is conducted to validate the numerical results. It is found that the maximum discrepancy between the simulation results and experiment values is 19.0%