高速切削加工表面粗糙度的研究

【作者】 邹浩波；

【导师】 张宇；

【作者基本信息】 昆明理工大学 ， 机械设计及其理论， 2006， 硕士

【摘要】 以高效率和高精度为基本特征的高速切削加工技术,是近20多年来迅速崛起的先进制造技术之一。高速切削加工具有非常高的生产效率,并可显著地改善零件的加工质量。 然而,仍然存在许多因素制约着高速切削加工技术的进一步发展与广泛的应用。高速切削加工作为一种新的切削理念,迄今为止,还没有系统的高速切削刀具材料的选择方案,也没有完整的加工参数可供选择。 现在高速切削加工时,切削参数的选择主要还是依靠经验,或者进行大量的试切试验,造成巨大浪费。如何选择合理的与工件材料相匹配的刀具材料、合理的切削加工工艺参数,以获得最佳的表面质量、延长刀具寿命、提高生产率、降低加工成本,成为目前高速切削加工的主要问题。 本论文通过对高速切削加工关键技术的研究,在理论上分析总结了现有的适用于高速切削加工的刀具材料,并根据高速切削刀具材料与加工对象的匹配原则(主要包括两者的力学性能、物理性能和化学性能相匹配),指出了适于高速切削加工各种工件材料的刀具材料。本文以铸铁为例,选择与之相匹配的刀具(Mapel公司的CBN刀具),基于正交试验法的原理,研究高速铣削加工铸铁工件表面时表面粗糙度的问题。选择合理的切削加工工艺参数(包括切削速度、切削深度和每齿进给量)作为试验因素,利用极差分析方法分析试验结果,指出各个因素对表面粗糙度影响的主次顺序,并确定最优的切削生产条件;利用方差分析的原理,根据方差分析表,对因素进行显著性检验,并给出置信度和置信区间;再利用回归分析方法,建立了表面粗糙度的预测模型,并对该模型的回归方程和系数进行了显著性检验。该模型能够精确预报高速铣削工件的表面粗糙度。 最后通过验证试验,分析验证了一些规律,即随着切削速度的提高,表面粗糙度会降低;而进给量的增加,会导致表面粗糙度的增加。为提高加工表面质量和刀具寿命、降低刀具成本提供依据,并推动我国高速切削加工技术的发展与应用。更多还原

【Abstract】 High-speed cutting machining (HSM) technology, based on the high efficiency and the high accuracy, is one of the advanced manufacture technologies, which has rapidly developed for more than 20 years. HSM has the extremely high production efficiency, and can remarkably improve the processing components quality.However, there still are many factors, which restrict the further development and the widespread application of HSM technology. As a new cutting idea, the HSM does not have the systemic choice plan of cutting tool material in HSM, and also does not have the integrated processing parameter to be chosen until now.The choice of cutting parameters, when high-speed cutting processing, mainly depended on the workers experience, or carried on massive cutting trials, resulting in the huge waste. The present main questions of HSM applications are how to reasonably choose the cutting tool materials, which match with the work piece materials, and the reasonable machining craft parameters, in order to obtain the best surface quality, to lengthen the cutting tool life, to enhance the productivity, and to reduce the product costs.By research on the key technologies of HSM, this paper theoretically analyzes and summarizes the existing tool materials, which are suitable for HSM. And according to the match principles of cutting tool materials and work piece materials, mainly included dynamics performance, physical performance and chemistry performance, point out the cutting tool materials, which are suitable for high speed to process each kind of work piece materials. This article takes cast iron as the example, chooses the cutting tool (Mapel Corporation’s CBN cutting tool), which matches with cast iron. Based on the principle of orthogonal experimental design, do the research on the surface roughness when high-speed milling cast iron with CBN. Select the reasonable machining craft parameters (including cutting speed, depth of cut and feed rate) as the experimental factors, make use of the range analytical method to analyze the trialresults, and point out the primary and secondary influence order of each factor to the surface roughness, and determine the most superior cutting condition. And use the analysis of variance (ANOVA) principle to determine which cutting parameters significantly affect the surface roughness. According to ANOVA table, carry on significant test to the factors, and come into being the confidence and the confidence interval. Again use the analysis of regression method, establish the forecast model of surface roughness, and carry on significant test to the regression equation and the coefficient of this model. This model can forecast the surface roughness when high speed milling.Finally, according to the confirmation experiment, conclude certain rules. That is along with the enhancement of cutting speed, the surface roughness reduce;but increase the feed rate, cause the surface roughness increase. The research on surface roughness of high-speed milling workpieces can provide the basis of enhancing the surface quality and cutting tool life, and reducing the cutting tool cost, and can impel the development and the application of HSM technology in China.更多还原