Authors: Jian Yun Shen, Wei Min Lin, Hitoshi Ohmori, Xi Peng Xu
Abstract: In the present study, natural granites were ELID ground with metal-resin bonded diamond wheels on a lap-grinding machine to achieve smooth surface. The surface roughness during the grinding process and final glossiness were examined to describe the formation of finely finished granite surfaces. According to the detailed micro-observation of ground surfaces, it can be concluded that natural granite surface on the main mineral components can be smoothly finished with ELID lap
grinding. However, the appearance of natural defects and residual fracture on the ground surface lead to the scattered surface roughness, and restrict the improvement of surface glossiness.
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Authors: Jian Yun Shen, Wei Min Lin, Hitoshi Ohmori, Xi Peng Xu
Abstract: In the present study, zirconia ceramic, crystal and two typical natural granites were ELID ground on a precision grinding machine under the same condition. The surface appearances during the grinding process with different mesh size metal bonded diamond wheels were examined to describe the formation of finely finished granite surfaces. According to the detailed micro-observation of ground surfaces, it can be concluded that the material removal mechanism of the main mineral components for natural granites are really similar to other brittle materials during ELID grinding process. However, the differences of material performances cause the granite materials to be larger critical grain depth of cut and more ductile during finely grinding.
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Authors: Bo Zhao, Yan Wu, C.S. Liu, A.H. Gao, Xun Sheng Zhu
Abstract: On the basis of analyzing the brittleness, ductileity, and the removal mechanisms of the^nano-ZrO2 Ceramics, the critical ductile grinding depth formula of the nano-ceramics was established. Due to superductileity of the nano-ZrO2 ceramics, it couldn’t apply the formula of the common engineering ceramic material according to experimental results. The value of material coefficient ζ has relations with not only the material characteristics but also the processing methods and the processing parameters. It was proved that ζ has great effects on the accuracy of theoretical
calculation. Experimental results showed that the critical ductility grinding depth of the nano-ZrO2 ceramics is up to 12 µm in common grinding methods, while in ultrasonic grinding is up to 20µm. The grinding chips with and without ultrasonic vibration assistance were discussed.
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Authors: Yi Yi Tao, Jiu Hua Xu, Wen Feng Ding
Abstract: The machining performance of porous NiTi shape memory alloys prepared using powder
metallurgical production technique has been investigated experimentally in the grinding operation.
Grinding force ratio, specific grinding energy, surface characteristics were detected. The result
reveals that, much difference of grinding characteristics exists among three kinds of NiTi alloy
because of the pore rate and the mechanical performance induced by TiH2. Under the experimental
conditions, the integrated effects of predominant plastic flow and slight brittle fracture were taken
for porous NiTi alloy during grinding. Additionally, the grinding parameters should be chosen
carefully, otherwise the surface quality deteriorates and even the microcrack perhaps appears.
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Authors: Hong Xia Zhang, Wu Yi Chen, Xiu Zhuo Fu, Li Xia Huang
Abstract: The present investigation was dedicated to elucidate grinding characteristics during surface grinding of titanium alloy(TC6) and high temperature alloy (GH2132) by using silicon carbide(SiC) and sol-gel (SG) wheel respectively. The grinding characteristic of SG wheel on aeronautical alloys was studied on the base of systematical measurement of the grinding force, grinding temperature, surface roughness and grinding ratio. The results indicated that the SG grinding wheel possesses excellent grinding properties and is more suitable for grinding these aeronautical alloys compared with conventional abrasive tools. Finally, the grinding mechanism of new-typed SG wheel was unveiled on the base of the microcrystalline structure analysis of SG grains.
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