Error Compensation And Software Development For Machining Aeronautical Monolithic Components

Aviation aluminum is a good performance of light alloys. It has the property of high strength, heat resistance, corrosion resistance and other excellent features. It is widely used in aviation of overall structure because of its performance. In the field of aviation manufacturing, it is more and more used in the main load-bearing structure. Aluminum component becomes much bigger and much more complex. One of the boeing aircraft floor beams is more than12m, the aspect ratio is up to20:1. Aluminum has a large coefficient of thermal expansion of up to several tens of microns per meter in thermal expansion. There are many problems in machining aluminum overall structure.Such as temperature tolerance deformation and error deflection of thin-wall features. Aluminum component is low rigid structure, and has weak resistance to temperature changes. Its property makes it hard in high speed machining.Aluminum component is studied in this paper. A model of mathematical model for the aluminum alloy7050-T7451and2124-T851materials of linear expansion coefficient is established by combination of theoretical analysis, finite element simulation and experimental method. An Aluminum monolithic structure of temperature compensation system is invented based on CATIA/CAA secondary development in the environment of CATIA. It has achieved a particular temperature compensation for a pre-compensating an aluminum structure size and has succeeded in getting the exact size of the digital model of parts at a certain temperature. A milling process test in a particular parameters is designed for an aluminum thin-walled component. A deflection data is obtained for thin-walled sidewalls when it is underside constrained. To achieve deflection compensation in CNC machining process, different orders of Polynomial fitting principle, cubic spline interpolation principle, B-spline curve fitting principle etc. is studied. With the help of mathematical software Matlab, an active deformation compensation system is developed based on the geometric symmetry of the mirror the deformation data when milling the sidewall, a NC compensation is accomplished using the developed compensation system, an validation milling test is carried on using the same machine and same parameters.