| Titanium alloy has a widely used in aerospace, marine, medical and many other areas atpresent because of it has the machining performance of smaller density, higher specificstrength, better heat resistance and corrosion resistance, especially for Ti-6Al-4V of α+βtitanium alloys, has had the largely and widely used in the number of applications. However,the machinability of Ti-6Al-4V is poor. In the milling process, there is a higher millingtemperature, a larger unit milling force, chilled seriously, serious tool wear and so on. Becausethe particular properties of mechanical, physical and chemical, making integrated millingperformance of Ti-6Al-4V to reduce and having a disadvantage effect on good surfaceintegrity with parts.In order to improve the cutting processing of Ti-6Al-4V titanium alloy, the structure ofTi-6Al-4V titanium alloy in different heat treatment is regarded as the object of research, andin the same milling parameters and cutting conditions, conduct dry milling test respectivelywith samples of forging, and then set up the mechanical model of milling force meanwhileanalyses the influence on different heat treatment processes to the surface of integrity.Comprehensive consideration cutting characteristics and milling characteristics of Ti-6Al-4Vtitanium alloy, the research contents of the forecast mechanical model of milling force andsurface integrity as follows:This paper is adopted the orthogonal table L9(34) with four factor and three level toconduct this test on three typical metallographic structure distribution with Ti-6Al-4Vtitanium alloy. The analysis in milling parameters which is included the axial cutting depth ap(mm), each tooth feeding fz (mm/z), milling speed vc (m/min), radial cutting depth ae (mm)affect on the forecast mechanical model of milling force and the surface integrity. By utilizingthe algorithm of least squares establishes the multivariate linear regression equations of themilling parameters on the main milling force and the surface integrity, and then conductingthe regression analysis, obtained more accurate empirical formula of milling force and the surface integrity of Ti-6Al-4V titanium alloy under different heat treatment process. UseMATLAB statistical software, the significances of the regression equation and regressioncoefficients are testing. Consequently, analysis the best heat treatment processing of millingTi-6Al-4V and the optimum combination of milling parameters, and this paper also discussesthe different heat treatment process to the influence on the performance of milling Ti-6Al-4Vtitanium alloy and the statistics law between four milling elements and milling force andsurface integrity. Make it come true which includes the designing of heat treatment process,the prediction of the model with milling force and the optimization of milling parametersbefore processing, so that provide theoretical basis for practical production in processing.In addition, this paper adopts the fuzzy neural network model to simulate the millingforce prediction. Fuzzy neural network is combined with fuzzy logic and neural networkwhich can be applied to the modeling and simulation for dynamic system of milling force.The fusion body can make up shortage of fuzzy processing for neural network and defect oflearning for pure fuzzy logic which can also make up adverse effects of complex factors formilling force in the process of milling titanium alloy (Ti-6Al-4V) and improve the accuratedegree of establishing the mathematical model for milling force with using the dataprocessing of pure fuzzy. This article will utilize the algorithm of regularization of fuzzyneural network to establish the prediction model of neural network for milling force, considerof the processing parameters of milling force, design the data combination of milling test totrain the model of fuzzy neural network, simulate the milling force by using fuzzy neuralnetwork model. The results show that the use of regularization fuzzy neural network methodto establish the Ti-6Al-4V milling force prediction model is reliable... |
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