| Titanium alloy blade is a key component of aero-engine.Its machining accuracy and surface quality have an important influence on the performance and life of aero-engine.At present,the automatic precision grinding technology of blade robotic abrasive belt is developing rapidly with its unique advantages,but it also faces many problems to be solved.For example,the material removal amount of blade robotic abrasive belt constant force grinding system is staggered by technological parameters,elastic contact of contact wheel and other factors,so it is difficult to achieve quantitative material removal.For this,this article embarks from the micro abrasive,grinding process parameters based on material removal rule,using the Hertz contact theory,probability and statistics theory to explain the single abrasive material removal mechanism,further establish applicable provisions blade belt grinding material removal model,for the robot abrasive belt material removal mechanism of prediction and analysis of constant force grinding system provide a new way.The research work of this paper mainly includes:(1)According to the research status of sand belt material removal prediction,four kinds of abrasive particle shape models,including spherical shape,spherical cone shape,regular tripyramid shape and regular tetrapyramid shape,were proposed by observing the micro-morphology of abrasive particles through ultra-deep field digital microscope and electron microscope equipment.The relationship between the cutting height of abrasive particles and the normal grinding force was established according to the effective number of abrasive particles per unit area,the function of abrasive edge height and Hertz contact theory.Based on the above methods,a material removal prediction model considering the occurrence probability of different shapes of abrasive particles was proposed.The model comprehensively considered the process parameters and grinding belt parameters,and could be adapted to the material prediction of different types of grinding belt.(2)Construct platform for titanium alloy grinding block,for TC4(Ti-6-Al-4V)robotic belt grinding of titanium alloy material experiment,analysis of the process parameters and sand strip environment the influence law of material removal and surface quality,at the same time,the mathematical model in this paper,the experimental verification,the results show that the model along the grinding path of material removal depth model,RMSE(Root Mean Square Error)is 2.86,MAPE(Mean Absolute Percentage Error)is 18.26%,the material removal rate model RMSE is 1.85,MAPE is 15.01%,the material removal depth model perpendicular to the direction of the grinding path X axis RMSE is 1.81,MAPE is 10.37%,The prediction results are in good agreement with the experimental data,which verifies the effectiveness of the proposed model.(3)Based on the grinding experiment of TC4 test block,the blade grinding experiment was carried out to verify the material removal depth model proposed in this paper.RMSE and MAPE of the model were 4.83 and 13.92%,indicating that the model could well predict the material removal of blade sand belt.It is of great significance to predict material removal in blade robot constant force grinding system.Through the research on the above contents,the exploration of robot belt material removal mechanism can make up for the lack of accurate control in the process of quantitative material removal in belt grinding,and it is of great significance to realize accurate removal and automatic grinding of blade constant force grinding system. |
PDF Full Text Request