To investigate the impact of interfacial layer effects on the thermal conductivity of nanofluids and the microscopic mechanisms of enhanced thermal conductivity, this study employed non-equilibrium molecular dynamics to compute the thermal conductivity, number density, radial distribution function, and mean square displacement distribution of SiC nanofluids. The impact of nanoparticle volume fraction and particle size parameters on the thermal conductivity of nanofluids and the structure of interfacial adsorption layers was discussed. The simulation calculation results show that the coefficient of thermal conductivity of nanofluid is positively related to the volume fraction of nanoparticles, increasing from 0.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
November 2023
Aiming at the difficulty of traditional machining of YO-ZrO (YSZ) inert ceramic materials, a different method using focused ion beam to selectively create nanoscale microscale structures on the surface of materials was proposed. The sputtering yield, surface damage, and the energy loss of YSZ materials was investigated using the SRIM software using the Monte Carlo method. It is shown that the sputtering yield increases with ion energy in the range 0-30 keV, reaching a maximum of 9.
View Article and Find Full Text PDFCutting force in lathe work is closely related to tool wear and affects the turning quality. Direct measurement of the cutting force by measuring the strain of the tool holder is challenging because the tool holder design aims to be highly rigid in order to undertake large cutting forces. Accordingly, the most popular dynamometer designs modify the standard tool holder by decreasing the structural rigidity of the holder, which reduces the machining precision and is not widely accepted.
View Article and Find Full Text PDFThe addition of CaF@SiO and SiC whiskers to ceramic tools can improve their flexural strength and fracture toughness, reduce surface damage, and improve their cutting performance. The cutting experiments showed that under the same cutting conditions, the surface roughness of the workpiece processed with the AlO/TiC/SiC/CaF@SiO (ATSC10) tool was significantly lower than that of the workpiece processed with the AlO/TiC/ SiC (ATS) tool. Additionally, the main cutting force and cutting temperature when cutting with the ATSC10 tool were lower by 30 and 31.
View Article and Find Full Text PDFCutting heat conduction undergoes three stages that include intensity transient-state, transient-state, and steady-states. Especially during machining with coated cutting tools, in the conduction process, cutting heat needs to pass through a few micron thick coatings and then flow into the tool body. This heat conduction presents typical non-Fourier heat conduction characteristics.
View Article and Find Full Text PDFAnal Bioanal Chem
April 2021
Colorectal cancer (CRC) is associated with one of the highest rates of mortality among cancers worldwide. The early detection and management of CRC is imperative. Biomarkers play an important role in CRC screening tests, CRC treatment, and prognosis and clinical management; thus rapid and sensitive detection of biomarkers is helpful for early detection of CRC.
View Article and Find Full Text PDFIn this paper, the Voronoimosaic model and the cohesive element method were used to simulate crack propagation in the microstructure of alumina/graphene composite ceramic tool materials. The effects of graphene characteristic size and volume content on the crack propagation behavior of microstructure model of alumina/graphene composite ceramics under different interfacial bonding strength were studied. When the phase interface is weak, the average energy release rate is the highest as the short diameter of graphene is 10-50 nm and the long diameter is 1600-2000 nm.
View Article and Find Full Text PDFThis study aimed at improving the cutting performance of a ceramic tool to which were added solid lubricant particles. We prepared the self-lubricating ceramic tool by adding CaF@AlO instead of CaF, and the self-lubricating ceramic tool with AlO as matrix phase, Ti(C,N) as reinforcement phase. The properties of the ceramic tool with different contents of CaF@AlO and CaF were studied by turning 40Cr.
View Article and Find Full Text PDFThe lubrication performance of graphene used as additive in 4-n-pentyl-4'-cyanobiphyl liquid crystal (5CB) for steel/steel contacts was studied on a ball-on-plate tribotester. The friction test results show that when the graphene content in the 5CB was 0.15 wt.
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