Life Analysis And Structural Parameter Optimization Of Tenon Broach For A Small Turbine Disk

Aeroengine is a sophisticated and complex machine that provides flight power for aircraft.Turbine disk and turbine blade are the core components of aeroengine,and they are connected by the groove of turbine disk.The manufacturing precision of groove directly affects the service life of the aeroengine.Broaching is currently the only processing method for groove machining of small sized turbine disk.Designing and manufacturing high-performance broaches is the key technology to obtain high-precision turbine disk.In the process of processing domestic broaches,there are problems such as non-wearability of broaches and poor surface quality.Therefore,it is necessary to carry out research on the life of the turbine disk groove broach and the optimization of the broach structure.This paper takes a certain type of small-sized superalloy turbine disk groove broach as the research object,and studies the groove broaching and broach wear process.The simulation technology is used to simulate the influence of the groove processing quality is studied.The key factors of broach are analyzed;the key factors affecting the life of the broach are obtained by anal yzing the wear pattern and mechanism of the broach;from the perspective of prolonging the service life of the broach,the structure and parameters of the broach are optimized and designed.The main research contents of this paper are as follows:(1)Analyze the fir-tree-shaped groove machining process of the small-sized turbine disk,including the groove shape,machining allowance distribution and broach structure.Establish a finite element model of the broaching process,define basic parameters of materials,set boundary conditions for simulation analysis,design broaching process tests,and verify model reliability and simulation accuracy.(2)The micro-morphological observation was carried out on the wear area of the broach edge,and the wear area of the front and flank surfaces of the broach was analyzed to find out the main forms of broach wear.Electron microscope was used to carry out energy spectrum analysis and X-ray surface scanning of the main wear area of the broach to find out the mechanism of broach wear.The wear process of the broach is studied,and the optimal design criterion of the broach based on the service life is obtained.The results show that the flank face of the broach is the main area of wear,and the wear of the flank face is mainly adhesive wear.The core of improving the service life of the broach is to reduce the temperature of the cutting edge and the broaching force during the broaching process.(3)Through finite element simulation analysis,the influence of broach structure on broaching force and temperature was studied.A multi-factor orthogonal test was designed,and the optimal structural parameters were obtained by analysis: broach tooth lift 0.02 mm,rake angle 20°,relief angle 3°,and cutting edge radius 0.005 mm.(4)The optimized broach edge parameters are adopted,and the broach tooth structure is optimized by chamfering the sharp corners on both sides of the broach edge.The broaching test was carried out on the vertical broaching machine,and studied the wear of the optimized broach.The result shows that the life of the optimized broach is significantly improved.