超声振动辅助磨削完全烧结氧化锆陶瓷牙冠的实验研究

针对现有全锆牙在制作过程中存在二次烧结、收缩精度难以控制等问题，提出了采用超声振动辅助磨削完全烧结氧化锆陶瓷牙冠的方法。从理论分析的角度对其运动学特性进行了研究，并通过超声振动辅助磨削和普通金刚石磨削实验，对该方法的可行性进行了分析。结合牙冠的加工特点，重点研究了主轴转速对材料去除率、表面粗糙度以及最大边缘碎裂的影响规律。实验结果表明，超声振动辅助磨削不仅能提升材料的去除率，有效抑制出口边缘碎裂，同时降低了工件表面的粗糙度，是实现完全烧结氧化锆陶瓷牙冠高效低损伤加工的新方法。

Test on Ultrasonic Vibration Assisted Grinding of Presintered Zirconia Crown

According to the machining problems for zirconia ceramics dental prosthesis which were exposed, such as complex process, difficult to control shrinkage and so on, a new method which used ultrasonic vibration assisted grinding presintered zirconia ceramics was proposed. Firstly, the macro kinematic characteristic is investigated from theoretical analysis. Then, an experimental study on machining presintered zirconia ceramics with ultrasonic vibration assisted grinding and diamond grinding is conducted to analysis the feasibility for the new method. Effects of spindle speed on material removal rate, surface roughness and edge chipping size are obtained, according to the machining characteristics of dental prosthesis. The experiment results demonstrate that the assistant for ultrasonic vibration not only increases the material removal rate, but also reduces the surface roughness and restrains the edge chipping effectively. Therefore, ultrasonic vibration assisted grinding might be the high efficiency and low-damage method for presintered zirconia ceramics.