Effect of Sintering Parameters and Liquid Phase Content on the Properties of Fe-Rich Based Impregnated Diamond Bit Matrix

The effects of sintering parameters and liquid phase content on the properties of Fe-rich based pre-alloyed impregnated diamond bit (IDB) matrix were investigated using orthogonal experimental design. Based on the analysis of the results, it was found that sintering temperature and liquid phase content have significant effects on the bending strength, hardness, relative density, and wear rate of the matrix. For metal matrix composite (MMC), as the sintering temperature increased from 900 to 1050°C, the bending strength, hardness (HRB), and relative density of the MMC decreased first, then increased, and finally decreased again, while the wear rate increased with temperature. With increasing liquid phase content, the four properties of the MMC showed a similar trend of increasing first and then decreasing. Comparatively, the effects of holding time and sintering pressure on the properties of the matrices were smaller than those of sintering temperature and liquid phase content, but they also had significant effects on some properties of the matrices. Holding time had a more significant effect on hardness and wear resistance, while sintering pressure only had a significant effect on hardness. After adding diamonds, the bending strength of diamond matrix composite increased first and then decreased with increasing temperature, while the bending strength continued to decrease with the increase of liquid phase content. This study provides a feasible method for studying the effects of various sintering parameters and liquid phase content on the properties of Fe-rich pre-alloyed IDB matrix, which is helpful for optimizing the preparation process of drill bits.