飞秒激光加工液体火箭发动机喷注部件无锥度微孔试验研究

In order to improve the micro-hole processing quality of liquid rocket engine injection components and completely eliminate the taper of hole wall, a rotary drilling method for inclined workpiece with changing the incident angle of laser and hole wall is proposed. The device platform for workpiece space regulation is designed and built. The influence of inclination angle and laser incidence orientation on the size and structure morphology of micro-holes is studied, and the evolution of inclined processing micro-holes is explored. A complete set of rotary drilling technology for inclined workpiece with fixed hole diameter and fixed taper is developed for centrifugal nozzle tangential holes. The results show that it is necessary to ensure that the laser optical axis and the workpiece rotation axis are coplanar during inclined processing, otherwise the hole curve error will be generated; the drilling taper can be controlled by adjusting the inclination angle of the workpiece, and the drilling radius can be controlled by adjusting the distance between the laser focus and the rotation center of the workpiece surface. The method realizes the non-taper deep holes processing with the depth of 4.5 mm and aspect ratios of 10:1. The micro-holes have good quality and no heat affected zone or recast layer on the surfaces and wall. The requirements of controllable high-quality processing of the tangential hole of the centrifugal nozzle of the liquid rocket engine may be satisfied.