Direct Bonding of Small Parts by Means of Ultraprecision Microgrooving Technology

本研究提出一种利用超精密V形微槽在两个小零件表面进行粘接的新方法，该方法无需使用任何胶粘剂。这些V形微槽允许小部件由于楔形效应和配合表面之间的粘附现象而以高定位精度结合在一起。通过使用具有1nm定位分辨率的超精密加工中心和金刚石铣刀来产生超精密V形微槽。主要研究内容如下：1.结果表明，键合强度一般随楔角的减小而增大。楔长对粘结强度的影响随楔角的变化而变化，楔角大于8度时，粘结强度随楔长的增加而增加，楔角小于8度时，粘结强度随楔长的减小而增加.这些V形微槽的深度和角度分别为20 μm和13.5度，由于楔形效应和两个配合表面之间的粘附现象，可以使小零件紧密结合在一起，具有高定位精度。3. 4 mm * 4 mm * 4 mm的小尺寸零件在两个方向上都有V形微槽，定位精度可达0.380 μm.这种新方法有可能将不同的材料相互粘合在一起。对由无氧铜和无氧铝制成的两个带有V形微槽的小零件进行了键合试验。结果表明，该方法能够有效地实现小零件的精确连接.实验表明，微槽加工技术同样适用于各种菲涅耳透镜和光学元件的加工。

The study proposes a new method of bonding two small parts without the use of any adhesive by making use of ultraprecision V-shaped microgrooves on the surfaces of each part. These V-shaped microgrooves allow small parts to be bonded together with high positioning accuracy due to a wedge effect and an adhesion phenomenon between the mating surfaces. Ultraprecision V-shaped microgrooves are created by using an ultraprecision machining center having 1 nm positioning resolution and a diamond milling cutter. The study is summarized as follows :1. It is found that the bonding strength in general increases with decreasing wedge angle. The effect of the wedge length on bonding strength though varies with the wedge angle where the strength increases with increasing length for wedge angles greater than 8 degrees but increases with decreasing length for wedge angles less than 8 degrees.2. These V-shaped microgrooves, whose depth and angle are 20 μm and 13.5 degree respectively, allow small parts to be tightly bonded together with high positioning accuracy due to a wedge effect and an adhesion phenomenon between two mating surfaces.3. Small parts of 4 mm * 4 mm * 4 mm that have V-shaped microgrooves in two direction could be tightly bonded with 0.380 μm positioning accuracy.4. The new method has a possibility to bond different materials each other. Two small parts with V-shaped microgrooves that are made of oxygen-free copper and aluminum are subjected to bonding test. As a result, the proposed bonding method is found to be effective to connect small parts accurately.5. It is experimentally found that the microgrooving technology is also applicable to manufacture various Fresnel lenses and optical elements.