Theoretical And Experimental Investigation Into Surface Generation In Ultra-precision Milling

With the continuous development of manufacturing technology,ultra-precision processing technology is gradually known to people.However,as the increase of processing cost,high-precision and high-quality,the processing of a single workpiece often needs a lot of time.Therefore,it becomes very difficult to obtain as many experience parameters as possible in a short time.In addition,due to the particularity of ultra-precision machining,the tool used is often very different from the traditional machining tool.So,the morphology of the final machined surface also needs to be further analyzed and studied.Firstly,by analyzing the motion process of a single point diamond ball milling cutter and using the copying principle of cutting edge,a surface generation model based on the geometric structure of the cutter and its cutting process is established.This reveals the basic process of ultra-precision milling.On this foundation,the influence of tool position deviation caused by production and assembly on surface generation is analyzed and explored.Then,by using the spindle multi-spring damping system,the simplified harmonic vibration model of the spindle is analyzed.And the influence of the spindle vibration on the milling surface is described.In addition,in the ultra-precision milling process,because of the extremely small cutting thickness,the elastic recovery of the material can't be ignored.The minimum chip thickness is the most important parameter to investigate the elastic recovery of materials.In this paper,ABAQUS(finite element simulation software)is used to ascertain the tool blade radius of 0.3 times the minimum chip thickness of brass materials.Then a surface generation model considering the vibration of the spindle and the elastic recovery of materials is established.Finally,through the milling experiment,the surface generated morphologies of several groups were obtained.And compared with the output results of the surface generated model,the two achieved good consistency.To sum up,the basic motion of milling cutter in ultra-precision milling is the main influencing factor of surface generation.However,the influence of spindle vibration and material elasticity recovery on surface generation cannot be ignored.