Study on WC-Co-Diamond-Based Composites Used in Cutters of Drill Bits
Inserts of drill bits used in perforation of wells are employed to cut many different kinds of stone. The material that shows the best performance on this application is the WC+Co+Diamond composite, obtained via powder metallurgy. However, heterogeneous microstructural aspects in these composites may impair their efficiency. On this work, WC+6%Co-based composites were obtained via high pressure sintering at 5.0 GPa, with diamonds, WC and Co powders. The particle size of the diamond was 400/315 μm, and for the WC and Co, 100/63 μm. Part of the samples also received 2wt%CrB2 as a doping agent. Wear tests were carried out in an abrasimeter with a maximum axial load of 50 kg. Linear and volumetric wear indices achieved values of 821∙10-6 g/m and 10.7 g/m3, that are superior to inserts produced via conventional powder metallurgy.
Lucio Salgado and Francisco Ambrozio Filho
G. S. Bobrovinitchii et al., "Study on WC-Co-Diamond-Based Composites Used in Cutters of Drill Bits", Materials Science Forum, Vols. 660-661, pp. 489-494, 2010