钎焊金刚石孔钻基体结构优化的实验研究

摘要

使用镍基合金焊料和45#钢基体,采用高温真空钎焊技术,制备了φ6mm的金刚石小孔钻,进行了基体结构的单因素对比试验,实现了多层钎焊效果,并进一步优化了孔钻基体的结构尺寸.在玻化砖钻削试验中,使用Hand USB Microscope和SEM跟踪观察了金刚石孔钻的磨损情况.结果表明:三种优化基体结构制作的金刚石钻头均出现了多层钎焊效果；该钻头比普通单层钎焊钻头多了三个磨损阶段,钻削寿命提高了70％以上；基体开槽的宽度是影响钻头多层钎焊效果的关键因素,以槽宽为金刚石粒径尺寸的2～3倍为宜.%Φ6 mm diamond core drills are made by using nickel-alloy solder and 45# steel through hightemperature vacuum brazing.The single factor experiment is designed to optimize the steel substrate structure.These drills are tested by drilling polished ceramic tile,and the wear patterns of diamond drills are recorded with Hand USB Microscope and SEM.The effects of all three kinds of multi-layer brazed diamond drills with different steel substrates are observed,and these drills are found to have three more wear stages and 70％ longer working life than the normal drills.Moreover,the key factor to realize the multi-layer brazed diamond effect is the width of the slots,and the comparatively proper width should be between twice and three times the size of diamond grit diameter.