陶瓷微细加工过程中的刀具磨损研究
发布时间：2018-12-30 21:31
【摘要】：陶瓷材料具有高强度、高硬度、耐高温、耐磨损、抗腐蚀等很多优异性能,随着微机电系统的发展,微小型零件需求的增加,陶瓷制品的应用前景越来越广泛。致密化烧结后的陶瓷坯体由于强硬度较高而难于加工,目前使用较广泛的加工方法是特种加工如电火花加工、超声波加工、激光加工等。但是其工艺复杂设备昂贵,快速成型方法的精度又比较低,同时陶瓷生坯直接加工由于强度较低又使其难以加工成型,严重影响所加工结构的质量。所以,寻找一种适合陶瓷材料加工的方法十分必要。本文在对陶瓷坯体预烧结的基础上,使用三维铣削加工的方法获得目标结构。所谓的预烧结就是将陶瓷生坯在低于完全烧结的温度下进行烧结,使其具有一定的强度,便于切削加工的顺利进行。利用线电极电火花磨削加工方法制备所需的微细刀具,编制数控加工程序,结合主轴的旋转和进给运动能够加工出不同截面形状的刀具如半圆形、三角形、四边形等,对预烧结陶瓷坯体进行三维微结构加工。微细刀具的磨损对于铣削加工的进行以及微结构的加工质量有很大影响,所以研究刀具的磨损现象十分重要。在预烧结陶瓷坯体上进行了一系列的微型腔结构的加工,研究了不同加工参数条件下,其中包括微细刀具的截面形状、预烧结坯体的强度、铣削加工层厚、加工转速以及加工速度等,微细刀具的磨损形态以及磨损量的大小,根据刀具的轴向和径向磨损程度的大小以及所加工的微型腔的质量选择出适合此微细铣削加工的实验参数。使用优化的实验加工参数,加工了三种不同尺寸的微型腔,测量了加工过程中的加工间隙以及刀具的磨损量。加工间隙就是刀具与所加工微型腔侧壁间的间隙。刀具的磨损量主要指轴向磨损量,刀具的磨损量由相对体积损耗率来衡量。在上述实验结果的基础上,计算得出该实验条件下的加工间隙以及相对体积损耗率的大小,然后对所加工微型腔进行尺寸补偿,获得了较高的加工精度。研究结果表明,补偿加工后的微型腔尺寸与目标尺寸十分接近,证明了补偿方法的可行性。
[Abstract]:Ceramic materials have many excellent properties, such as high strength, high hardness, high temperature resistance, wear resistance, corrosion resistance and so on. With the development of micro electromechanical system and the increasing demand of micro parts, the application prospect of ceramic products is more and more extensive. It is difficult to process ceramic billet after densification and sintering because of its high hardness. At present, special machining methods such as EDM, ultrasonic machining and laser machining are widely used. However, the complex process equipment is expensive, the precision of rapid prototyping method is low, and the quality of the machined structure is seriously affected because of the low strength of ceramic blank and the difficulty of processing it. Therefore, it is necessary to find a suitable method for ceramic material processing. In this paper, the target structure is obtained by three dimensional milling on the basis of presintering of ceramic billet. The so-called pre-sintering is to sintered the raw ceramic billet under the temperature of complete sintering, so that it has a certain strength, which is convenient for the smooth processing of cutting. By using the method of wire electrode EDM, the micro cutting tools are prepared, and the NC machining program is compiled. Combined with the rotation and feed motion of the spindle, the cutting tools with different cross-section shapes such as semicircle, triangle, quadrangle and so on can be machined. The three-dimensional microstructure of pre-sintered ceramic billet was processed. The wear of micro cutting tools has great influence on the milling process and the machining quality of micro structure, so it is very important to study the wear phenomenon of cutting tools. A series of micro cavity structures were processed on the presintered ceramic billet. Under different processing parameters, including the cross section shape of fine cutting tool, the strength of presintered billet, the thickness of milling machining layer, the microstructure of presintered ceramic billet was studied. According to the axial and radial wear degree of the cutting tool and the quality of the micro-cavity, the experimental parameters suitable for the micro-milling machining are selected according to the machining speed and speed, the wear pattern and the wear amount of the micro-cutter. Three kinds of micro cavities with different sizes were machined with optimized experimental processing parameters. The machining clearance and tool wear were measured. Machining clearance is the gap between the cutting tool and the machined micro cavity side wall. Tool wear mainly refers to axial wear, and tool wear is measured by relative volume loss rate. On the basis of the above experimental results, the machining gap and the relative volume loss rate under the experimental conditions are calculated, and then the size compensation of the micro-cavity is carried out, and the higher machining accuracy is obtained. The results show that the size of the micro-cavity is very close to the target size, which proves the feasibility of the compensation method.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG71
[Abstract]:Ceramic materials have many excellent properties, such as high strength, high hardness, high temperature resistance, wear resistance, corrosion resistance and so on. With the development of micro electromechanical system and the increasing demand of micro parts, the application prospect of ceramic products is more and more extensive. It is difficult to process ceramic billet after densification and sintering because of its high hardness. At present, special machining methods such as EDM, ultrasonic machining and laser machining are widely used. However, the complex process equipment is expensive, the precision of rapid prototyping method is low, and the quality of the machined structure is seriously affected because of the low strength of ceramic blank and the difficulty of processing it. Therefore, it is necessary to find a suitable method for ceramic material processing. In this paper, the target structure is obtained by three dimensional milling on the basis of presintering of ceramic billet. The so-called pre-sintering is to sintered the raw ceramic billet under the temperature of complete sintering, so that it has a certain strength, which is convenient for the smooth processing of cutting. By using the method of wire electrode EDM, the micro cutting tools are prepared, and the NC machining program is compiled. Combined with the rotation and feed motion of the spindle, the cutting tools with different cross-section shapes such as semicircle, triangle, quadrangle and so on can be machined. The three-dimensional microstructure of pre-sintered ceramic billet was processed. The wear of micro cutting tools has great influence on the milling process and the machining quality of micro structure, so it is very important to study the wear phenomenon of cutting tools. A series of micro cavity structures were processed on the presintered ceramic billet. Under different processing parameters, including the cross section shape of fine cutting tool, the strength of presintered billet, the thickness of milling machining layer, the microstructure of presintered ceramic billet was studied. According to the axial and radial wear degree of the cutting tool and the quality of the micro-cavity, the experimental parameters suitable for the micro-milling machining are selected according to the machining speed and speed, the wear pattern and the wear amount of the micro-cutter. Three kinds of micro cavities with different sizes were machined with optimized experimental processing parameters. The machining clearance and tool wear were measured. Machining clearance is the gap between the cutting tool and the machined micro cavity side wall. Tool wear mainly refers to axial wear, and tool wear is measured by relative volume loss rate. On the basis of the above experimental results, the machining gap and the relative volume loss rate under the experimental conditions are calculated, and then the size compensation of the micro-cavity is carried out, and the higher machining accuracy is obtained. The results show that the size of the micro-cavity is very close to the target size, which proves the feasibility of the compensation method.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG71
【共引文献】
相关期刊论文 前4条
1 于化东;张留新;许金凯;于占江;;微小车床刀具磨损检测方法[J];长春理工大学学报(自然科学版);2014年02期
2 周志雄;肖航;李伟;黄向明;;微细切削用微机床的研究现状及发展趋势[J];机械工程学报;2014年09期
3 李秋s，
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