Papers by Author: Chao Liu

Abstract: This study selected three types of organic substance as the main components of high-efficient organic grinding liquid for grinding ceramics with silicon. The grinding efficiency test was conducted on the basis of self-developed grinding mechanism and the findings indicated that the grinding performance of all these three types of grinding liquid were better than average grinding liquid. With Si3N4 Ceramics as the representative test material, the grinding efficiency can be increased at least 1.37 times and more than twice with the grinding fluid prepared with oleic acid or oleic alcohol. The analysis of liquid-solid interface with the help of infrared spectrum showed that there existed abnormal vibration peaks in the liquid-solid interface between Si3N4 ceramics and grinding liquid with (organic substances)–OOH and －OH under normal temperature, which resulted from the adsorption effect of hydrogen bond generated between organic molecule and Si3N4 ceramics. Under high grinding temperature, the friction chemical reaction took place as the result of the absorption effect and the resultant could not only reduce the surface hardness, but also improve the lubricating effect, thus improving the grinding efficiency and surface quality.

Abstract: With reference to the principle that the strong detonation wave generates the transient dynamic high pressure, the small power pulse power supply and the electrode micro-detonation wave generator are developed. The engineering ceramic material machining with low cost is realized successfully with the devices. It is shown from the study results that there is a degenerative layer about 0.25~0.45mm thick, which is composed of amorphous phases and crystalloid Si and can be machined and removed with the ceramic tool after micro-detonation machining. There are obvious transverse cracks near the interface of the degenerative layer and the matrix, but the cracks along the depth direction are not found. The performance of the degenerative layer is roundly analyzed and its removing mechanism is primitively discussed.

Abstract: Based on the comprehensive summary of latest research achievements of Laser and EDM technologies in home and abroad, the other advanced machining technologies is summarized briefly, such as Ultrasonic Wave, Microwave machining techniques and their composite machining technologies, as well as High-speed (Super High-speed) Grinding, ELID Grinding and Interface Thermal Chemistry Reaction Aided Machining technologies developed on the basis of traditional grinding technology. At last, it is forecasted that the necessary direction of advanced technologies used for ceramics is combinatorial machining technologies of two or more kinds of advanced technologies.