Research On Electrolyte-plasma Deburring Technology Of Aircraft Engine Blade

Electrolyte plasma processing technology is capable of doing polishing and deburring process on the surface of metal which have a complex shape. Compared with the traditional deburring and polishing technology, it has a higher efficiency, lower cost and less pollution to the environment. It is generally difficult to remove the burrs of aircraft engine blade inner surface by conventional methods, making it imperative to find a method to remove the burr of inner surface. In order to solve this problem, this thesis has made a research on the technology of aircraft engine blade plasma electrolyte deburring, which is aimed at finding the best way to remove aircraft engine blade burrs with electrolyte plasma technology, improving surface quality and laying the foundation for further research.The thesis has described macroscopic and microscopic mechanism of electrolyte plasma deburring process. From the perspective of the metal oxidation, the thesis has described that planarization and deburring process is the result of both plasma physics effect and chemical reactions. From the perspective of volt-ampere characteristic, the thesis has described two different processing methods of electrolyte plasma deburring, and has selected a better method to do subsequent tests.The electrolyte plasma deburring test platform for blade has been built: It has analyzed the surface structure of aircraft engine turbine blades, and has established a three-dimensional model of aircraft engine turbine blades; It has selected superalloy parts and superalloy parts with complex inner cavity as typical specimen to do initial tests, and has analyzed the feasibility of engine turbine blades deburring; On the basis of the engine turbine blade model, it has designed dedicated fixture for turbine blade deburring using polypropylene as the main material; Besides, it has built flow control system for engine blades deburring, laying the foundation for further study.Orthogonal experimental design has been done on the test platform using TA2 titanium tube as a test object. In the designing process, it has selected inner surface roughness at the entrance of hole and surface roughness value of 40 mm from the entrance of the hole as evaluation indexes; it has also selected the processing temperature, the processing time, the inflow rate of the hole and the spatial angle as the influencing factors. By analyzing the test results, the thesis has obtained the primary and secondary order of each influencing factor and optimum processing parameters. Based on this optimal parameters, it has done preliminary electrolyte plasma deburring tests for aircraft engine turbine blades, and it has found that the plasma layer had been produced between the workpiece and flowing electrolyte, and burrs are removed by discharge effect. After testing, it has found that the blade wall damage, remelted layer removal, the intercrystalline corrosion and external film cooling holes rounded state have reached a more satisfactory result. A three factors and three levels orthogonal experiment has been designed by selecting single-crystal parts as specimens. T he design has selected surface roughness as an evaluation index, it has also selected processing temperature, processing time, div ing depth as influencing factors. By analyzing test results, the thesis obtained the optimal process parameters. By comparing specimens before and after electrolyte plasma processing under optimal process parameters, it is found that the surface roughness is reduced from the original Ra 1.29 μm to Ra 0.6 μm, and surface microscopic projections has been significantly reduced, thus the surface quality has been improved.