Gas compensation-based abrasive flow processing method for complex titanium alloy surfaces

To resolve the problems of uniformity and efficiency of soft abrasive flow (SAF) processing for complex titanium alloy surfaces, a gas compensation-based abrasive flow (GCAF) processing method is proposed. By the constrained modules, an enclosed flow passage covering the titanium alloy surface is built up, in which the gas phase is injected to enhance the turbulence intensity of abrasive flow. Taking the constrained flow passage as the objective, a three-phase fluid mechanic model for GCAF is set up based on the realizable k-e model and the mixture model. The profiles of velocity and dynamical pressure of abrasive flow field in the constrained flow passage are obtained, and the turbulence variation regulars caused by gas compensation are revealed. Numerical results show that the proposed method can strengthen the turbulence intensity of abrasive and improve the distribution uniformity of dynamical pressure. A GCAF processing experimental platform is developed, and the experiments are performed. The results prove that the proposed method can obtain better processing efficiency and uniformity, the average surface roughness is less than Ra 0.3, and the surface topograph of micro-peak and micro-valley can reach less than 50 and 10 μm, respectively.