脉冲激光修锐青铜金刚石砂轮烧蚀机制研究

青铜金刚石砂轮具有优良的磨削性能，在初次使用和磨损后必须对其修锐。由于青铜结合剂和金刚石磨粒之间存在热物理、光学性质的差异，可通过选择合适的脉冲激光功率密度去除结合剂，凸出磨粒，实现选择性去除。针对声光调Q YAG脉冲激光修锐青铜金刚石砂轮，建立了适合激光烧蚀青铜结合剂的实际过程的传热与气化动力学模型，运用数值计算模拟出各种激光功率密度下的熔层温度、熔层厚度和烧蚀速率，进而获得激光功率密度与激光烧蚀凹坑深度的关系，并与实验结果进行比较。通过验证表明所建立的模型可以正确描述实际物理过程。

Ablation Mechanism of Bronze-Bonded Diamond Wheels Dressing by Pulsed Laser

Bronze bonded diamond wheel is superior grinding performances. It has to be brought into dressing for grinding before its first use or when reaching the service life criterion. Due to the thermal physical and optical differences between bronze bond and diamond abrasive, suitable pulse power density is selected to remove bonds and protrude thus realizing the selective removal. A heat transfer and gas dynamic model was created to describe single pulsed laser ablation which was occurred in the experiments of dressing bronze-bonded diamond wheel by acoustic-optic Q-switched YAG pulsed laser. The average temperature and thickness of melted layer, ablation velocity and depth by different laser power densities was calculated with numerical method. The model is proved to be correct by contrast with the experiment result.