Determination of Friction Coefficients at Elevated Temperatures for Some Al, Mg and Ti Alloys
The results of research on friction conditions of alloys: magnesium Mg4AlZn, titanium Ti6Al4V and aluminum 6101A are presented in this paper. The aim of these research was determining values of friction factors and coefficients, which characterize constant friction model and Coulomb's model within the range of hot metal forming temperatures at various lubrication conditions. In the research works the ring tests were applied. For the alloy Mg4AlZn the samples were heated to the temperatures: 250°C, 350°C and 450°C, for aluminum alloy 6101A to the temperatures: 350°C, 400°C, 450°C and for alloy Ti6Al4V to the temperatures: 850°C, 900°C, 950°C. Tests were made in conditions of friction without lubrication and with the application of lubricants: tallow with graphite, Aquagraphite CP, Lubrodal-F318 and on the basis of molybdenum disulfide.
Friction factors and coefficients values were determined on the basis of comparison of experimental research results wih results of the conducted tests simulations. The value of factor and coefficient which guaranteed the best convergance of theoretical and experimental dimensions of upset samples was assumed as optimal. On the basis of the obtained results the influence of temperature on friction conditions and effectiveness of the used lubricants were determined in relation to analyzed alloys.