【作者】 陈国桂；

【导师】 陈根余；

【作者基本信息】 湖南大学 ， 机械工程， 2009， 硕士

【摘要】 青铜金刚石砂轮具有异常优良的磨削性能,在难加工材料的磨削、精密磨削、高效磨削和磨削自动化中有广泛的应用前景。近年来,由于砂轮制造问题得以突破及陶瓷、玻璃等难加工材料应用增多,青铜金刚石砂轮应用急剧增加。由于金刚石硬度极高,传统、单一的“硬碰硬”修整方法不适合青铜金刚石砂轮的修整,严重影响了其优良磨削性能的充分发挥。基于微区热作用的激光烧蚀微细加工修整已被广泛认为是一种非常有发展前途的方法。本文基于三角测量原理,通过确定合理的试验方案、选取理想的结构参数和接收透镜,设计了一套激光光路系统,加工了一套较为精密三角测量装置。进行了单脉冲激光烧蚀青铜金刚石砂轮试验,研究了激光功率密度、平均功率、脉冲重复频率和离焦量对青铜金刚石砂轮烧蚀效果的影响。通过分析单脉冲激光烧蚀试验后的砂轮表面形貌图,找到了激光精密修整试验所需的最合适激光参数。进行了激光修整砂轮的可行性分析,研究了声光调Q脉冲激光修整青铜金刚石砂轮的机理。采用PSD作为光电检测元件,研究了PSD的工作原理,从理论上推导了输出电压U0与圆跳动X之间的线性关系。用二维精密位移台的微量进给模拟砂轮表面圆跳动,对微位移量与输出电压信号之间的关系进行了标定。试验结果表明:U0与X成线性关系,标定结果与理论值吻合,从而验证了三角测量系统和检测电路的准确性。将三角测量系统和检测电路应用于激光烧蚀系统标定试验,其标定结果为下一步激光精密修整试验做好了准备。直接以加工激光作为光学三角检测光源,即检测光源与加工光源合二为一,以保证砂轮的测量位置与加工位置一致。同时根据激光烧蚀系统标定的结果来调整比较电压,分粗修和精修两步进行砂轮精密修整试验。用体视显微镜观察分析了修整后砂轮表面形貌图。最后研究了激光-机械复合精密修整技术,砂轮修整精度得到了进一步的提高。该技术适合于磨粒尺寸较大的青铜金刚石砂轮精密修整。更多还原

【Abstract】 With excellent grinding performance, the Bronze-bonded diamond wheels have a wide application prospect in the field of precision, ultra-precision, high efficiency grinding, grinding automation and difficult processing material forming. In recent years, because of the breaking through of the grinding wheels manufacture question and the increasing application to difficult processing materials such as ceramics, glasses and so on, Bronze-bonded diamond wheel’s application growth sharply. Because of the ultrahigh hardness of diamond, it’s difficult for traditional truing and dressing method which was based on the interaction of force to promot. which really affects the grinding performance of Bronze-bonded diamond wheels. A new method which to solve problems of truing and dressing Bronze-bonded diamond wheel fundamentally truing has attracted much attention all over the world.A set of laser triangulation system based on three angular measurement mensurations has been designed in this paper. The reasonable testing program has been determined, the reasonable design parameter and the appropriate optical elements are selected. The experiment of a single pulse ablation on a bronze-bonded diamond wheel has been carried out. The relationship between the ablated effect and some different laser ablating parameters such as laser intensity, power intensity, repetition frequency and focal position, has been analyzed. The ablated topographies of the wheel were observed, obtained the appropriate laser parameters to truing and dressing wheel. analyzed the bronze-bonded diamond grinding wheel truing and dressing mechanism by laser.Using PSD as the electro-optic detecting element, the principle of work of PSD has been analyzed. Using the microfeed of the 2-D precision positioned to simulate the precise circle beat of the grinding wheel surface, the linear relationship between U0 and X in theory is derived. Demarcation is carried on to the relationship between the micro displacement and the output voltage signal. Test results showed that: the relationship between U0 and X is linear. The results of calibration coincide with the theoretical value, and the accuracy of triangulation system and detection circuit is verified. Then the triangulation system and detection circuit are used in the laser ablation system demarcation experiment.Which are prepared for the next precision laser test. To make the surveys position and its integration with the optics triangulation, the processes laser is used for triangular surveying directly, and the light source of examination and processing is made into one. According to the results of calibration, adjusting the comparison voltage. we have choosen reasonable laser process parameters for the experiment and analyzed the truing and dressing topographies in each kind of experimental parameter by video microscope.The precisely truing and dressing technology of laser-machinery which is suitable to truing and dressing Bronze-boned diamond wheels with bigger abrasives in size, which will be studied in further.更多还原