Research On Surface Quality Of Superalloy GH4169 Machined By ECM & EDM

As a kind of preferred material, which the constructive parts of aeronautical & astronautical vehicle are made of, superalloy GH4169 has been attractive day by day for its good special characters in high temperature environment and can be widely used in the constructive parts of aeroengine, also will be applied to some important micro constructive parts of micromotor and micro aerial vehicle. However, superalloy materials have some special characters such as small thermal conductivity , serious work hardening in manufactured process , large cutting force, which appear to be very difficult to cut for some traditional machining methods. So nontraditional machining method, such as ECM & EDM, will have special advantage in machining superalloy material.Many facts have been shown that more and more failures of aeronautical & astronautical parts had been resulted from its outer surface, and then gradually extended to its inner zone. Surface quality will have great effect not only on its functional performance such as assembly quality, fatigue strength, resistance to wear, and corrosion resistance and so on, but also on the total equipment's longevity and its reliability. However surface quality is relative to the machining method and its machining parameter. In other words, the good surface quality will be produced by selecting the suitable machining method and machining parameter. So it is very important to make a research on the producing principle and process of the surface quality machined by ECM & EDM.The research status, the main content of surface quality of GH4169 machined by ECM & EDM and its function affected on the part longevity are briefly introduced in this paper. A certain sets of superalloy GH4169 samples were machined by ECM & EDM with different machining parameters, then the relative surface quality are systematically measured and analysed. The main research contents are as follows:(1) The effect of surface quality of superalloy GH4169 machined by ECM at different current density is investigated. Also the effect and the function on the microstructure of superalloy GH4169 at different current density are analyzed.(2) The surface quality machined by EDM at different types of parameter is investigated and analyzed. Under a certain machining conditions, including selecting the suitable machining parameters, designing the suitable process and processing allowance, the good surface quality and high product efficiency can be made. In conclusion, the main factor and its changed rule of surface quality machined by ECM & EDM will be found through the above investigation, which will become the important reference for making the good surface quality in production engineering of aeronautical & astronautical parts.