Effect of Lubricant Type on the Friction Behaviours and Surface Topography in Metal Forming of Ti-6Al-4V Titanium Alloy Sheets

Abstract

The aim of the research described in this paper is to analyse the synergistic effect of types of synthetic oil and their density on the value of the coefficient of friction (COF) of Ti-6Al-4V titanium alloy sheets. Lubrication performance of commercial synthetic oils (machine, gear, engine and hydraulic) was tested in a strip draw friction test. The friction tests consisted of pulling a strip specimen between two cylindrical fixed countersamples. The countersamples were placed in the simulator base mounted on a uniaxial tensile test machine. Due to the complex synergistic effect of different strip drawing test parameters on the COF, artificial neural networks were used to find this relationship. In the case of both dry and lubricated conditions, a clear trend was found of a reduction of the coefficient of friction with nominal pressure. Engine oil 10W-40 was found to be the least favourable lubricant in reducing the coefficient of friction of Grade 5 titanium sheets. The two main tribological mechanisms, i.e., galling and ploughing, played the most important role in the friction process on the test sheets. In the range of nominal pressures considered, and with the synthetic oils tested, the most favourable lubrication conditions can be obtained by using a type of oil with a low viscosity index and a high kinematic viscosity.

Modelling of Friction Phenomena Existed in Drawbead in Sheet Metal Forming

“…The viscosity of the HD 1150 compound is η = 1157 mm 2 ·s −1 , while the viscosity of the LAN-46 oil is η = 43.9 mm 2 ·s −1 . The strip specimens were lubricated using a teflon shaft [ 11 , 62 ]. The amount of lubricant applied to each of the two surfaces of the samples was 2 g/m 2 [ 11 , 62 ].…”

“…The strip specimens were lubricated using a teflon shaft [ 11 , 62 ]. The amount of lubricant applied to each of the two surfaces of the samples was 2 g/m 2 [ 11 , 62 ]. During the test the lubricant is squeezed out between the countersample surface and the sheet surface.…”

Suppression of the High-Frequency Errors in Surface Topography Measurements Based on Comparison of Various Spline Filtering Methods

“…The textures analyzed in this paper have been widely used in mechanical, automobile, and chemical departments due to their toughness, excellent wear resistance, performance stability, and other considerable advantages [ 70 ]. The ceramic ground surface was analyzed, and the surface topography ceramic femoral head was previously studied [ 71 ], the geometric structure of the rough surface is connected to many engineering problems, e.g., sealing, friction [ 72 ], or wear [ 73 , 74 , 75 ]. Despite that, the engineering ceramic surface is generally different from the metal surface after machining.…”

The Influence of the Shielding-Gas Flow Rate on the Mechanical Properties of TIG-Welded Butt Joints of Commercially Pure Grade 1 Titanium

“…Titanium is a ductile alloy that can be formed by sheet metal methods [ 8 ] or other plastic working techniques [ 9 ]. Due to the hexagonal close-packed crystal structure, titanium alloys exhibit a low ductility and formability at room temperature [ 10 ]. However, at elevated temperatures, the titanium and Ti-based alloys can be successfully formed [ 11 ].…”