Effect of Fe mass fraction on diamond bit′s matrix and drilling properties

Fe-Cu matrix formulas were designed to research the effect of Fe mass fraction on diamond drill bit's matrix and drilling properties.Hardness,relative density and three-point bending strength of different formulas' sintered samples were analyzed.The fracture appearances of these sintered samples were investigated by SEM.The drilling efficiency and service life of different formulas' drill bits were analyzed by drilling simulations.The results show that each formula's sample can be well sintered,and that their relative density can reach up to more than 98% of theoretical density.The hardness increases first,and then decreases while Fe mass fraction increases.The hardness tends to be steady when the mass fraction of Fe increases to more than 45%,and it reaches the maximum as 35 HRC at 60% Fe.The three-point bending strength result shows that it does not change obviously but in a small range.The fracture appearance SEM shows that the toughness decreases and the diamond etching effect aggravates while Fe mass fraction increases.Drilling simulations show that the 30% Fe formula sample perform better,both in drilling efficiency and service life,when drilling 6to 8level drill ability stratum.