Magnetorheological finishing apparatus

Abstract

Fluid Jet Polishing (FJP) is a kind of ultra-precision machining technology which not only becomes more widely used for removing tool marks, in order to achieve super finished surfaces while controlling the form accuracy, but also becomes more widely used in superfinishing freeform surfaces made of difficult-to-machine materials. The material removal characteristics, which are described as a tool influence function and assessed in terms of width, maximum depth and material removal rate, play an important role in simulating the surface generation accurately and manufacturing the designed surfaces deterministically in FJP. Due to the multi-factor influence and the complexity of the polishing mechanism, it is difficult to model the material removal characteristics accurately with the consideration of a lot of operational parameters in FJP. In this paper, a ductile-mode erosion model has been built to predict the volume removed by a single particle and a modified Gaussian function was used to describe the spatial distribution of abrasive particles in Fluid Jet Polishing. Hence, an Integrated Computational Fluid Dynamic (CFD)-based erosion model was established which integrates the CFD model, erosion model and experimental study to predict the material removal characteristics in FJP. A series of experiments were conducted by the a Zeeko IRP200 Ultra-precision Computer Controlled Polishing machine so as to validate the predictability of the integrated CFD-based erosion model. The experimental results show a good agreement between the model predicted results of CFD-based erosion modelling.