The temperature responses at the toolworkpiece interface during circular sawing of a typical gray natural granite with diamond segmented blades were measured by using a foil thermocouple consisting of two thin foils sandwiched in a split workpiece specimen. The sawing experiments were conducted in a down cutting mode on a bridgetype experimental sawing machine. Scanning electron microscope and optical microscope were employed to observe the morphologies of diamond grits and their bonding with the metal matrix.The measured results, taking into account the net sawing power,were fitted with the theoretical counterparts so as to estimate the heat partition transferred to the granite and the segments,using a temperature matching technique. Based on the heat partition value obtained from the experiments, the diamond tip temperature was calculated. As the results, more than 90% of the heat generated at the cutting zone was conducted to the diamond segments during the dry sawing. The tip temperatures at a part of the diamond grits on the segment surfaces were possibly above 1000℃. The three typical wear modes of the diamond grits, namely, mechanical wear, fracture, and pullout, were closely related to the heat generated during the sawing process. When the diamond grits were coated with TiCr alloy before sintering, strong metallurgical bonding was observed between the diamond grits and the metal matrix. Thus TiCr coating was effective in restraining the heat induced pullout of the diamond grits.