Ultrafine diamond (UFD) is produced at high pressure and high temperature generated by explosive detonation. We manage to search for a new technology to purify the UFD by using potassium permanganate and concentrated ...Ultrafine diamond (UFD) is produced at high pressure and high temperature generated by explosive detonation. We manage to search for a new technology to purify the UFD by using potassium permanganate and concentrated sulfuric acid as oxidant. The experiment results show that, compared with others, the purifying effect by this technology is satisfactory and is a more efficient, cheaper, and safer purification technology with less pollution and less investment. It can be put into commercial use. The related principle of the technology is discussed. It is believed that the atomic state oxygen produced during the reaction mechanism is an active substances which would react with the graphite——the main impurity existing in the detonation soot, and the reaction temperature is the key factor in the process.展开更多
Surface modification of Diamond-like carbon (DLC) films was carried out in order to estimate the reliability of the ultra thin DLC films. The wear resistance, conductivity and mechatronic reliability of the films were...Surface modification of Diamond-like carbon (DLC) films was carried out in order to estimate the reliability of the ultra thin DLC films. The wear resistance, conductivity and mechatronic reliability of the films were studied by contact atomic force microscope (AFM), electric force microscope (EFM) and conductive AFM. The failure mechanism of pits formed and the reason for conductivity changed of DLC films were examined.展开更多
Nanometer chips were directly fabricated using face nanogrinding carried out by ultrafine diamond grits at room temperature. Direct evidence for ground nanometer chips is cuboid, and the average ratio of width to thic...Nanometer chips were directly fabricated using face nanogrinding carried out by ultrafine diamond grits at room temperature. Direct evidence for ground nanometer chips is cuboid, and the average ratio of width to thickness is 1.49. Chips of 9.0 nm in thickness, 13.3 nm in width, and 16.0 in diagonal were achieved and confirmed using transmission electron microscopy. Based on the nanometer chips observed, a model was proposed according to the mass conservation and fundamental mechanism of face grinding. The surface roughness and thickness of damaged layers measured experimentally are in good agreement with the prediction of the developed model. The feed rate significantly affects the surface roughness and thickness of damaged layers, when keeping the wheel and table speeds constant, respectively.展开更多
文摘Ultrafine diamond (UFD) is produced at high pressure and high temperature generated by explosive detonation. We manage to search for a new technology to purify the UFD by using potassium permanganate and concentrated sulfuric acid as oxidant. The experiment results show that, compared with others, the purifying effect by this technology is satisfactory and is a more efficient, cheaper, and safer purification technology with less pollution and less investment. It can be put into commercial use. The related principle of the technology is discussed. It is believed that the atomic state oxygen produced during the reaction mechanism is an active substances which would react with the graphite——the main impurity existing in the detonation soot, and the reaction temperature is the key factor in the process.
文摘Surface modification of Diamond-like carbon (DLC) films was carried out in order to estimate the reliability of the ultra thin DLC films. The wear resistance, conductivity and mechatronic reliability of the films were studied by contact atomic force microscope (AFM), electric force microscope (EFM) and conductive AFM. The failure mechanism of pits formed and the reason for conductivity changed of DLC films were examined.
基金supported by the National Natural Science Foundation of China (Grant No. 91123013)Tribology Science Fund of State Key Laboratory of Tribology (Grant No. SKLTKF12A08) (Tsinghua University)+1 种基金Fund of State Key Laboratory of Metastable Materials Science and Technology (Grant No. 201302) (Yanshan University)the Fundamental Research Funds for the Central Universities (Grant No. DUT13YQ109)
文摘Nanometer chips were directly fabricated using face nanogrinding carried out by ultrafine diamond grits at room temperature. Direct evidence for ground nanometer chips is cuboid, and the average ratio of width to thickness is 1.49. Chips of 9.0 nm in thickness, 13.3 nm in width, and 16.0 in diagonal were achieved and confirmed using transmission electron microscopy. Based on the nanometer chips observed, a model was proposed according to the mass conservation and fundamental mechanism of face grinding. The surface roughness and thickness of damaged layers measured experimentally are in good agreement with the prediction of the developed model. The feed rate significantly affects the surface roughness and thickness of damaged layers, when keeping the wheel and table speeds constant, respectively.
