The wear mechanisms of impregnated diamond bits

Abstract

Impregnated diamond (ID) bits are rotary drag bits, which are specifically dedicated to drill hard and abrasive rock formations. Performing like a grinder wheel, the cutting face ID bits is continuously evolving during drilling, exposing new and sharp diamonds. The performance and the life of these bits are thus controlled by an integrated and complex wear process. To better understand the wear mechanisms of ID bits, a series of drilling and cutting tests were conducted with ID core bits and segments at CSIRO's Drilling Mechanics Laboratory. The results have indicated that the evolution of ID cutting face is characterized by different patterns or wear mechanisms, depending on the depth of cut imposed. At shallow depth of cuts, the wear is predominantly dominated by diamond polishing and erosion of the binder, and at higher depth of cuts, the wear is controlled by diamond fracturing and matrix abrasion.