WC添加对热压铁基预合金粉末胎体性能的影响

Effect of WC addition on properties of hot pressed iron baseprealloyed powder matrix

摘要:

针对孕镶金刚石钻头在强研磨性地层中磨损快、寿命短的问题，利用WC硬度高、润湿性好、耐磨性好的特点，向铁基预合金粉末中添加WC颗粒作为胎体骨架金属。通过测试不同WC含量的胎体试样的硬度、抗冲击韧性以及抗弯强度，寻找骨架金属WC对胎体性能的影响规律。试验结果发现，随着WC含量的逐渐增加，胎体的硬度、抗冲击韧性、抗弯强度均呈现先增大后减小的变化趋势。从微观和能量的角度出发，分析了出现这种规律的原因。最后得出烧结温度为830 ℃、WC含量为5%时，胎体的性能达到最优，此时胎体的强度和研磨性最大。

Abstract:

In order to tackle the problems of fast wear and short life of impregnated diamond bit in abrasive formation, the WC was added to iron base prealloyed powders as matrix metal owing to the characteristics of high hardness, high wettability and good abrasion resistance of WC. The hardness, impact toughness and bending strength of the matrix sample with different WC contents were tested to find the influence law of the support metal WC on the matrix performance. The results show that with the gradual increase of WC contents, the hardness, the impact toughness and the bending strength of the matrix sample exhibit the same trend: increase first and then decrease. From the perspective of micro-structure and energy, the reason of this rule is analyzed. Finally，it is concluded that the matrix achieves the optimal performance when the sintering temperature is 830℃ and the WC content is 5%. In this case, the strength and abrasiveness of the matrix sample are the maximum.