Study On Titanium Alloy Surface Treatment Based On Abrasive Water Jet

For the surface treatment of the popular material titanium alloy workpiece,the traditional way of mechanical polishing,electrochemical polishing or manual polishing,none of this ways was the perfect method to work with the surface treatment,because their polishing accuracy and polishing efficiency aren't high,and all the ways are harmful for environmental protection and have high labor intensity for workers,meanwhile,the surface of the workpiece that has been polished is easily deformed and easily damaged.Therefore,this paper proposes a new method of polishing for titanium alloy workpiece based on abrasive water jet,and based on the material erosion removal mechanism of abrasive water jet,the analysis of the force of abrasive particles on the workpiece,combined with fluid erosion simulation and single-factor experiment,verifyingt the feasibility of abrasive water jet polishing for titanium alloy.In the end,orthogonal experiment are used to optimize the polishing process parameters and establishing a predictive model of surface quality.By testing the model,it is concluded that the abrasive water jet is feasible for polishing the surface of the titanium alloy workpiece.The specific content of this paper is as follows:(1)Background knowledge of abrasive water jet technology and mechanism of erosion material removal.First,based on the nozzle flow theory,a computeral simulation have done for optimizing the nozzle structure,it was concluded that the abrasive water jet polishing nozzle should use a streamline nozzle or a cone-straight nozzle.Then describing the basic structure and basic parameters of the abrasive water jet.In the end,for the polishing mechanism of abrasive water jet,the stress model of single abrasive particle on the material and the removal mechanism of the material are analyzed.(2)Aiming at five different process parameters(also known as simulation factors),namely jet pressure,target distance,impact angle,particle concentration and particle average diameter(abrasive particle size),using CFD numerical simulation software FLUENT to simulate the surface of the titanium alloy workpiece striked by abrasive water jet.Meanwhile,studying the force of the erosion surface of the workpiece and the velocity distribution of abrasive particles on the erosion surface of the workpiece at different levels of single process factor based on the control variable method.(3)Designing a single-factor experiment of control variate method,and using the experimental data to qualitatively study the effect of various process parameters on the surface quality of the polished titanium alloy workpiece.Theoretical analysis of the experimental results,and compared with the simulation analysis results,the conclusions are basically consistent with.(4)Using orthogonal experiment to optimize the five process parameters studied in this paper,and obtaining the optimal parameter combination for polishing the surface of titanium alloy workpieces.The regression analysis method in statistics is used for multivariate nonlinear curve fitting on the experimental data points to establish a predictive model of the surface quality of the titanium alloy workpiece.In the end,testing the model and analyzing the error.