Experimental and Numerical Analyses of Effect of Thermal Stability of Lubricants on Heatstreaks in Cold Rolling of Stainless Steel

Abstract

The numerical analysis model of temperature in a roll and a rolled material was first derived by solving the equations of heat conduction. Next, the occurrence limits of heatstreaks for reduction in thickness and interface temperature in a roll bite were evaluated experimentally and numerically in cold rolling experiments of stainless steel (SUS430) with two kinds of lubricants. Also, the thermal stability of two lubricants was measured by thermal balance experiments. Consequently, the limit of interface temperature due to heatstreaks calculated numerically is almost constant in a lubricant, which suggests that an outbreak of heatstreaks is mostly dependent on the thermal stability of lubricant. Also, larger quantity of synthetic ester is considered to give higher heatstreak resistance in cold rolling of stainless steel.