화학공학소재연구정보센터
Powder Technology, Vol.268, 150-157, 2014
A study on the vibration induced transport of nanoabrasives in liquid medium
Vibration Assisted Nano-Impact-machining by Loose Abrasives (VANILA) is an emerging process suitable for the target specific nanomachining of hard and brittle materials. Understanding the transport of nanodiamond powders in fluid is essential to determine the effective gap between the tool and the work surface in VANILA process. In this paper, various forces acting on the abrasive nanoparticle in aqueous slurry are analyzed. It is understood that transient cavitation force and acoustic streaming forces have the most dominating effects in causing the nanoparticle impact on the workpiece surface. A model to predict the impact velocity of the nanoabrasive grain on the workpiece surface is developed and it is found that during the machining process, an impact velocity in the order of 10(2) m/s is achieved, molecular dynamics simulation (MDS) is used to simulate the nanoparticle transportation during the process. The MDS study reveals that the machining gap during the VANILA process needs to be maintained at less than 200 nm for an abrasive grain size range of 5-20 nm. The MDS results are in conformance with the theoretical modeling results. (C) 2014 Elsevier B.V. All rights reserved.