Does intermittent mandatory ventilation correct respiratory alkalosis in patients receiving assisted mechanical ventilation?: Hudson LD, Hurlow RS, Craig KC, et al. Am Rev Respir Dis 132:1071, 1985

Abstract

Ductile-regime machining of brittle materials is a critical issue for ultra-precision manufacturing, because the machined surface is prone to be damaged by brittle fracture. Previous studies have showed that surface modification by ion implantation can be used to reduce the brittleness and improve the machinability. However, most researches focus on the formation of a continuous modified layer extending from surface to a specific depth. Although this configuration could provide a remarkable modification, it always requires a large ion dose and is time consuming. For this reason, a buried modified layer model is proposed in this paper. Firstly, the effect of the modified layer on crack propagation is studied by molecular dynamics simulation, which indicates an increase in fracture resistance of the buried modified layer model. Then, ion implantations are conducted on the (100) surface of silicon, and modification on the lattice structure is evaluated by Raman spectrum and transmission electron microscopy. Finally, diamond turning test is conducted and the critical undeformed chip thickness is measured. The results show that the buried modified layer is a potential configuration for improving the diamond turning process on brittle material.