The Processing Mechanism And Procedure Of Stongly Constrained Abrasive Jet Polishing On The Surface Of Hard Brittle Materials

This paper use the processing technology of strongly constrained abrasive jet,aim at solving the problem of hard and brittle materials' processing.In this study,theory,simulation,and experiment were used to study the processing mechanism and the procedure of the machining method of the strongly constrained abrasive jet.The main work and contents of this paper are as follows:(1)On the basis analyzing of the present research status at home and abroad,this paper analyzes the principle of strongly constrained abrasive jet processes,and the relations between the jet direction with the po int on the workpiece surface.Under the strongly constrained abrasive jet polishing processes,the jet impact on the workpiece with large angle,and the tangential grinding force increase,which improves the processing efficiency and accuracy.(2)According to the processing theory of strong constrained abrasive jet polishing,setting up the experimental platform.O n basis of ensuring the nozzle close to the workpiece surface,the arm drive the nozzle move along the workpiece in the radial direction and combined with the rotation of workpiece,so abrasive flow form a cross-like "plow" in the surface,achieve the purpose of smooth workpiece surface.(3)Based on hydrodynamics and jet mechanics,analyzing the force of abrasive and the motion of jet under the strongly constrained abrasive jet polishing processes.Analyzing the model of liquid-solid two-phase flow,and adopt the classical Eulerian model as numerical simulation models.And adopt the standard k-equation as the fluid simulation equations.Through the computation of Reynolds number,determining the motion of internal fluid and jet are turbulence.(4)The actual processing conditions as the simulation parameters in this experiment,and analyzing the nephogram of stress and speed about internal fluid and jet.The analysis showed that strong constrained abrasive jet processes can increase speed,increasing from the 1.82m/s to 6m/s,and the velocity of the jet tangent to the surface of workpiece,which agree very well with the theoretical predictions.(5)The result of this experiment verify the correctness of the simulation result,and get the conclusion from analyzing the experimental date : Firstly,under the condition of 1500 mesh abrasive and 15% abrasive density,the processing effects is the best.Secondly,the processing effect of jet outlet is better than the other position of the surface on the workpiece.(6)Building the material removal function.On the basis of analyzing the experimental data,building material removal function.Comparing the removal function with the scatterplot of the experimental data,verifying the accuracy of the function.In a word,the machining process of strongly constrained abrasive jet can solve problems of the water jet divergence and the damage of vertical impact force in the traditional water jet machining process.It also validates the feasibility of water jet processing and sets up a cutting materials function through the method of combination of simulation and experiment,which provides theoretical and practical support for the following research.