钎焊金刚石磨粒焊接强度

利用高频感应钎焊技术制备单层金刚石静强度实验样块和磨削砂轮,比较了单颗金刚石磨粒在磨削过程中所承受的平均法向和切向载荷分别与其钎焊后的静压强度和静剪切强度大小,结合对磨削过程中磨粒的磨损形态的观察,揭示钎焊金刚石砂轮在磨削过程中金刚石磨粒的磨损机理. 实验结果表明:一般磨削过程中金刚石磨粒所承受的载荷远小于其静强度;钎焊后磨粒的静强度主要受钎焊时的真空度和钎焊加热时间的影响,真空度越高,静强度越大,钎焊时间越长,静压强度损失越大,而静剪切强度却存在一个最佳的钎焊时间;利用高频感应加热方式制备金刚石工具的磨粒焊接强度,完全能满足一般磨削加工要求,在磨削过程中磨粒以微破碎为主,很少有脱落和整颗折断现象.

Welding strength of brazing diamond grits

Monolayer diamond grinding wheels and static strength samples were prepared by the HF induction brazing technology under different conditions.The normal abrasion behavior of diamond grits was found out through the comparison between the single grit's tangential and normal component force during grinding and the static compressive strength and static shearing strength of diamond grains after being brazed.As the same time,the abrasion state of diamond grits during grinding was observed.The results show that the load applied to diamond grains during grinding process is much smaller than their static strength after being brazed.The static strength of diamond grits after being brazed is influenced by vacuum degree and heating time during brazing process.The static strength is strong under the conditions of high vacuum degree and the static compressive strength loses much under the conditions of long brazing time.Otherwise,the static shearing strength is associated to an optimal brazing time.Diamond tools fabricated by the HF induction brazing technology meet the needs of normal grinding fields.Most of the grits are micro-broken during grinding and only a few of them are pulled-out or broken-off.