Papers by Keyword: Nano Machining

Abstract: Nano structures such as CNTs were proposed to be directly used as cutting grains to fully utilize the nice mechanical and thermal properties for nano machining. To further understand the CNT abrasive tool, a theoretical study of the CNT uncut chip model was conducted together with preliminary experimental tests to investigate the chip generation in the nano machining process. We found that the CNT distribution was not even in the CNT layer of the wheel. Based this finding, a grain spacing model and a feed of workpiece per cutting edge model were developed. Theoretical results were all very small. It was also found that individual workpiece chips were difficult to find due to small sizes. Further work is necessary. Furthermore, Chip gelling effect was found. The reasons were due to agglomeration and epoxy melting. Experimental results were found agree with our theoretical results.

Abstract: We propose to use nano structures directly to fully utilize the nice mechanical and thermal properties for nano machining. In this project, CNTs were directly used as cutting grains. For the CNT grains, we use epoxy as one of the bonding materials of our choice. A series of CNT grinding wheels were fabricated to demonstrate the effectiveness of the proposed new type of abrasive tool. Preliminary experimental tests were conducted for the proposed method of abrasive tool making. The CNT wheels are made of 1% MWCNTs or Multi Wall CNTs. Preliminary test results show that CNT wheels without functionalization or chemical treatment give the best average results. In the developed abrasive tool, CNT nano cutting edges are clearly seen in the TEM image. Carbon nanotubes can be used as cutting grains for nano machining. Further experiments are necessary.

Abstract: The confine of ductile-mode cutting and brittle-mode cutting seems to be a crucial step for designing a brittle material removal process. However, the existing transition from ductile-mode to brittle-mode for BK7 material makes the confine of different mode very difficult. Through a series of micro/nano-machining tests, measurements of cutting forces and morphological appearance of cutting groove as well as the cross section at the certain depth of cut, the confirmation of ductile-mode cutting, transition-mode cutting and brittle-mode cutting has been clearly described in the paper. This lays a foundation for the fundamental understanding of cutting physics concerning of material characteristics and cutting tools, and thereafter for the development of optimal process technology.