Friction and wear performance of Titanium alloy against tungsten carbide lubricated with phosphate ester

摘要

Due to the relatively low density, outstanding strength-to-density ratio and excellent corrosion resistance, titanium alloys have been widely utilized in aeroengine and airframe manufacturing fields [1,2]. However, titanium alloys are recognized as difficult-to-cut materials due to their low thermal conductivity, high chemical activity and small elastic modulus [3,4]. Cutting fluid is considered as an accessory in a machining process in order to increase the productivity. It lubricates the contact areas between rake face and chips, flank face and machined surface as well as reduces adhesion and abrasion thus producing a good surface finish. As to the mechanism of this action, the chemical compositions of the cutting fluid are of vital importance and the interactions with the metal surface have been investigated [5]. Researches try to find effective additives which have good tribological properties with steel or aluminum alloys, for example, borate ester compounds, phosphorus-containing molecules and so on[6,7]. However, the chemical properties of metal surfaces differ significantly. As a consequence, the type and intensity of interaction of cutting fluid additives with titanium alloys are very different with steel and aluminum alloys because of the bad tribological properties of titanium alloys [8]. Up to now, few reaches have been done to investigate the effective cutting fluid additives with titanium alloys considering the lubricating and anti-adhesion properties. This paper aims to provide an effective water soluble additive for titanium alloys and investigate the mechanism of the additives acting with the metal surface. It can be further used for the development of titanium alloys cutting fluid.