1. College of Construction Engineering, Jilin University, Changchun 130026, China;
2. Key Laboratory of Drilling and Exploitation Technology in Complex Conditions of Ministry of Natural Resources, Changchun 130026, China;
3. Faculty of Engineering, China University of Geosciences, Wuhan 430074, China;
4. National Center for International Research on Deep Earth Drilling and Resource Development, China University of Geosciences, Wuhan 430074, China

  In order to improve the matrix performance of impregnated diamond drill bit to better meet the drilling needs, the effects of the addition of nano-WC and nano-NbC particles on the matrix material together with the mechanical properties and microstructure of the diamond-matrix composite material of the Fe-based diamond drill bit were studied by using the method of uniform formula design, regression analysis and solution finding. An indoor drilling test was also carried out using the fabricated impregnated diamond drill bit. The results showed that after the addition of nano-NbC and nano-WC, the hardness and flexural strength of the matrix material got improved, as the flexural strength of the diamond composite material increased to 4.29%, the wear-resistance ratio increased to 8.75%, and the tighter the chemical bonding between the diamond and the matrix. This, indicates that the addition of nanoparticles has a positive significance in improving the performance of the diamond composite. The results of the drilling test showed that the mechanical drilling speed of the impregnated diamond drill bit after nanoparticle strengthening is 25.85% higher than that of the conventional drill bit, and the matrix wear was increased by 17.5%. It proves that nanoparticles can improve the drilling performance and efficiency of drill bit.