Research On The Fabrication Of Impregnated Diamond Drill Bit With Hybrid Nano Additives For Hard Rock Formations

With the global exploration focus shifting to deep mineral deposits,the need for deep hard rock drilling has increased in recent years.Hard rock formations pose a significant challenge to drilling operations due to their high strength and abrasiveness.The drilling industry is constantly looking for new ways to improve drilling efficiency and reduce the cost of drilling.One way to achieve this is by enhancing the strength and wear resistance of drilling tools,particularly for use in hard rock formations.Over the past few years,both domestic and international researchers have boosted the mechanical properties of metal matrix composites by introducing nano-materials.Based on certain investigations,it has been discovered that the addition of nano-materials in diamond tools can enhance the hardness,bending strength,wear resistance of the diamond tool matrix,as well as the matrix’s capability to receive diamonds,ultimately leading to a significant improvement in diamond tool performance.This study explores the effect of adding nano-sized ZrO₂ and VN particles on the mechanical properties of a WC-bronze-based impregnated drill bit.Scanning electron microscopy and X-ray diffraction were used to analyze the microstructure and phase composition of the drill bit.The mechanical properties,including hardness,compressive strength,and wear resistance,were evaluated using standard testing methods.The results showed that the addition of both ZrO₂ and VN nanoparticles improved the mechanical properties of the impregnated drill bit.M1 sample of blank matrix has the highest bending strength of 947MPa with a conspicuous reinforcement effect when compared with M0 sample.Specifically,the addition of 1 wt.%of ZrO₂and 0.5 wt.%of VN improved the bending strength of blank matrix and IDC by 27%and 12.5%,respectively.The bending strength of the IDC and grinding ratio is 477MPa and 1188 respectively.The wear resistance was significantly enhanced,with a34.8%wear ratio increase for M1-D（with nano additives）sample and 18.5%wear ratio decrease for M0-D（without nano additives）sample,respectively.Finally,a WC-bronze-based impregnated diamond bit strengthened by nano material was fabricated using the same concentration of sample with the best mechanical properties in diamond composite samples,and a laboratory drilling experiment was carried out.The test results showed that under the same drilling parameters,the ROP（rate of penetration）of the hybrid nano-reinforced impregnated diamond bit was 6.41 m/h,and the working layer wear rate was 1.5 mm/m.The ROP was 18.3%higher than that of the conventional diamond bit,and the matrix wear was reduced by 34.8%.Indoor drilling tests showed that the expected life of the drilling bit was 30 m,which is a 58%improvement.The field drill test showed that the average time efficiency of the test bit was 22.5%higher than that of the conventional drill bit,and the average life of the test bit was 1.55 times longer than that of the conventional drill bit.Overall,the addition of nano-sized ZrO₂ and VN particles can effectively strengthen the WC-bronze-based impregnated drill bit and improve its drilling performance in hard rock formations.