Direct Bonding of Small Parts by Means of Ultraprecision Microgrooving Technology

这项研究提出了一种新的方法，利用每个零件表面的超精密V型微槽，在不使用任何粘合剂的情况下将两个小零件连接在一起。由于楔形效应和配合表面之间的粘合现象，这些V型微槽允许将小部件粘合在一起，并具有高定位精度。利用1 nm定位精度的超精密加工中心和金刚石铣刀加工出超精密V型微槽。主要研究内容如下：1.研究发现，随着楔形角的减小，粘接强度总体上呈上升趋势。楔形长度对粘接强度的影响随楔形角度的不同而不同，当楔形角度大于8度时，强度随长度增加而增加，而当楔形角度小于8度时，强度随长度减小而增加。这些V型微槽的深度和角度分别为20μm和13.5度，由于楔形效应和两相配表面之间的粘合现象，可以将小部件紧密结合在一起，并具有高定位精度。4 mm×4 mm×4 mm的双向V型微槽的小零件可实现0.380μm的定位精度。这种新方法有可能将不同的材料相互粘结在一起。对由无氧铜和铝制成的两个带有V形微槽的小零件进行了粘接试验。结果表明，所提出的键合方法能够有效地实现小零件的精确连接。实验发现，微槽技术同样适用于各种菲涅耳透镜和光学元件的制造。

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.