In the present paper extrusion pressure is determined using Tresca’s criterion of yielding and Reynolds equation is solved thermally in consideration of viscous heating heating effect for the computation of thermal minimum film thickness of lubricant in the inlet zone using input data (Table-1). The minimum film thickness of lubricant in the inlet zone is a boundary condition for the solution of work zone and therefore real assessment of minimum film thickness in the inlet zone leads to perfect modeling of frictional behavior in the work zone. A comparison of thermal minimum film thickness in the inlet zone is done (Fig. 2) with Wilson & Mahadavian formula [Wilson and Mahadavian 1976] in which Barus viscosity model is assumed and results shows that a significant difference is observed in the present computational work. The thermal minimum film thickness of lubricant is found an increasing trend with the given viscous thermal parameter (Fig. 3) while for elevated viscous thermal parameter a reverse trend is also observed by the authors while thermal minimum film thickness decreases with increase of semidie angle of die. The variation friction stress decreases along the work zone (Fig. 4) due to excessive lubricant
pressure/more lubricant viscosity at the entry point and decreases on increase of viscous thermal parameter. The average friction factor increases on increase of semi-die angle (Fig. 5) and decreases on increase of viscous thermal parameter and extrusion pressure (Fig. 6) due to better lubricating conditions at the die/billet interface