Complex Thin-walled Parts In-situ Measurement And Evaluation Of Error Contour

The wing frame, impeller and blades are typical aerospace complex thin-walled parts, having a weak rigidity, difficult process, complicated profile processing difficulties.Such parts commonly used difficult materials superhard aluminum, titanium, etc. It will generate large cutting force, deformation of the workpiece, cutting regional resilience, structural flutter, resulting in machining accuracy is difficult to guarantee, when milling in the five-axis high-speed machining center. To solve these problems, this paper studied aeronautical thin-walled parts in situ measurement and evaluation contour error, for cutting a workpiece, measurement, compensation in-situ machine. The main contents include the following.(1) Setting up two kinds of in-situ measurement platform. One is based on Huazhong HNC-818B CNC system built in-situ measurement platform, the main advantage of the computing power of NC system itself, by invoking the measurement macro-situ measurement methods to achieve part of the solution to the original domestic CNC system can not bit technology bottleneck measurement; the other one is based on Heidenhain iTNC530M CNC system built in-situ measurement platform, the main advantage of the computing power of the PC, through third-party software PowerInspect measurement path planning to generate measurement procedures implemented method of in-situ measurement of parts, which can be easily and quickly complex part measurement point cloud inspection and planning contour errors.(2) Designing the wing frame type parts in-situ measurement and compensation processing experiments. Experiment analyse thin-walled parts cutting deformation with the software of Abaqus, propose error compensation method, write compensation software and in-situ measurement program, and complete the In-situ measurement and error compensation Experiments on NC Central XHK715 machine. Experimental results show that the compensation method for weak rigid component significant compensation effect, using aerospace aluminum 7075-T651 frame parts when the wall thickness of less than lmm accuracy improvement on average 44% of compensation. The frame parts compensation accuracy average increase of 44%, when the wall thickness of less than lmm with the use of aerospace aluminum 7075-T651; the frame parts compensation accuracy improvement on average 57%, when the wall thickness of less than 0.5mm with the use of titanium alloy TC4.(3) Putting forward a significant analysis method of optimization of cutting parameters for impeller. Experiments establish impeller model by software UG, complete cutting simulation in software Vericut, finish measurement planning and simulation measurements in software PowerInspect and In-situ measurement and orthogonal experiments on Mikron UCP800Duro machine. Experimental Range and variance analysis shows that the surface quality of primary and secondary factors affect the order:depth of cut> feedrate> cutting. Optimal cutting parameters experimentally obtained as follows:depth of cut 0.1mm, feed rate of 0.17mm/r, cutting speed 120m/min.(4) Completing blade situ detection and analysis of the experimental contour error. For different thickness, length of the blade design multiple sets of simulations, in-situ measurements and contour error analysis on the machine. It's found that the natural frequency of the blades decreases with increasing thickness of leaves, leaf length decrease with increased, namely leaflets thick, large leaves long blades in high-speed milling process prone to flutter, by controlling the spindle speed to avoid resonance region improve the surface quality. Experiments show that under the same cutting parameters, the average thickness of the dorsal blade machining error of 0.014mm, thin blade dorsal average machining error of 0.040mm.