Laser hole making device and method

Abstract

The invention relates to a laser hole making device and method. The hole making device comprises a laser source, a beam expander group, a laser self-rotating device and a scanning galvanometer device,wherein the laser source is used for outputting laser beams along a center axis of a conduction light path; the beam expander group comprises a convex lens and a concave lens, the separation distanceof which can be adjusted, and the laser beams passing through the beam expander group are incident to the laser self-rotating device; the laser self-rotating device is used for deviating the laser beams at an adjustable deviation radius to the center axis of the conduction light path to form a round ring facula, and the round ring facula is incident to the scanning galvanometer device; the scanning galvanometer device is used for rotating the round ring facula around the center axis of a focusing lens to form a plurality of concentric tracks, the focused tracks are used for scanning a processed hole to a target bore diameter after focusing, and the target bore diameter is preset. The laser hole making device can reduce the hole making tamper to improve the hole making efficiency and further can reduce influence of change of a focal position or a wall thickness to consistence of the bore diameter.

Description

technical field [0001] The invention relates to the technical field of laser processing equipment, in particular to a laser hole-making device and method. Background technique [0002] Ultrafast lasers usually refer to femtosecond (10 ps) pulse widths less than 10 ps. -15 s) Laser, picosecond (10- 12 s) Laser, because the action time is very short, the laser power density is extremely high (over 10 12 w / cm 2 ), so there is almost no thermal diffusion in the process of removing the material, and the material removal is non-thermal melting. Therefore, ultrafast laser can be used to process small holes with no heat-affected zone, recast layer, and micro-cracks on the hole wall. figure 1 . while milliseconds (10 -3 s) Laser processing of small holes with longer pulse widths is difficult to avoid the recast layer on the hole walls of the small holes, see appendix figure 2 . [0003] Air film holes in aero-engine single crystal turbine blades require no recast layer, micr...

AI Technical Summary

Problems solved by technology

[0004] However, the ultrafast laser pulse energy is very low, for example, the pulse energy of picosecond laser usually does not exceed 500μJ, resulting in low processing efficiency and large taper of small holes

The above phenomena greatly limit the practical application of ultrafast laser machining blade air film hole technology

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