▎ 摘　　要

Titanium and its alloys are difficult to machine due to their high chemical reactivity and poor thermal conductivities. One of the key challenges in machining titanium components is the making of high-quality holes which is driven by the demands from aerospace industry. This paper is focused on drilling titanium alloy (Ti-6Al-4V) with a new graphene oxide suspended cutting fluid. A series of cutting experiments were conducted to investigate the effects and working mechanisms of the new fluid. Thermal conductivities of conventional coolant and the graphene oxide suspended fluid was measured; the effects of different cutting parameters such as cutting speed and feed rate were analysed; thrust force, surface roughness, tool wear and the formation and morphology of chips were discussed. To investigate the performance of graphene oxide suspended cutting fluid, similar experiments were conducted with conventional coolant as well. A significant reduction in cutting force of up to 17.21% and a dramatic improvement in surface roughness of 15.1% were achieved by using the new graphene oxide suspended-cutting fluid. (C) 2017 The Society of Manufacturing Engineers. Published by Elsevier Ltd. All rights reserved.