Paper Title
Scratching Rate Effects on CERCHAR Abrasiveness Index of Sandstones

Abstract
The objective of this study is to determine the effects of scratching rate on CERCHAR abrasiveness index of three types of sandstone under dry and saturated conditions. Results from this study indicate that uniaxial compressive strength of rock has a direct effect on the CAI value. Linear equation can well describe the relation between rock strength and CAI value. Lower scratching rates will result in a deeper groove and lower scratching force on rock surfaces, and lower CAI value of the stylus pin. CAI for saturated rocks is lower than that of dry rocks. Effect of pore pressure for saturated rock will reduce when the scratching rate is decreased. Keywords - CERCHAR, Sandstone, Scratching groove, Wear, Tool.