Experimental investigations of jet impingement quenching for three different cylindrical blocks made of copper, brass and steel have been conducted with block initial temperature from 250 to 600 degrees C. Visible observations during the quench show that the wetted area can be divided into two regions - a central region with no apparent boiling and the outer annular region where the liquid boils vigorously. The width of the boiling region is of interest since there is a coupling between high heat transfer rates and the observed boiling pattern. Boiling width increases with material conductivity and decreases with jet sub-cooling and velocity. Boiling width is also influenced by the initial temperature of the solid. (c) 2008 Elsevier Ltd. All rights reserved.