Device and method for ultrafast laser processing of micro inverted cone hole

Abstract

The invention discloses a device and method for ultrafast laser machining of micro-inverted taper holes. The laser transmission module includes a picosecond laser, a frequency doubling module, a polarizer and a beam expander arranged in sequence along the transmission direction of the optical path. The optical processing module includes a The rotary cutting module and the optical nozzle are arranged in sequence in the transmission direction of the optical path, and the output end of the beam expander is connected to the rotary cutting module; the picosecond laser outputs laser light, which is converted by the frequency doubling module to output base frequency light, double frequency light or triple frequency light Light, the laser beam output by the frequency doubling module passes through the polarizer to convert the output wave form linearly polarized laser beam into a wave form circularly or elliptically distributed circularly polarized laser beam, and then the beam is transmitted into the beam expander for amplification , to obtain a wider parallel beam, the enlarged parallel beam is transmitted to the rotary cutting module, the rotary cutting module adjusts the deflection angle of the beam, controls the aperture size and taper of the processing hole, and finally outputs it through the light nozzle. It is easy to realize the processing of fine reverse taper hole.

Description

technical field [0001] The invention relates to a laser processing method, in particular to a device and method for ultrafast laser processing micro-inverted taper holes, and belongs to the technical field of laser micro-special processing. Background technique [0002] Under the trend of miniaturization and precision of the structure of mechanical parts, micro-inverted taper holes with high depth-to-diameter ratio are more and more used in aerospace, aerospace turbine blades, engine fuel injectors and precision instruments, and the precision requirements are also increasing. higher. For example, the fine inverted cone nozzle hole on the diesel engine nozzle can effectively improve the fuel combustion efficiency and reduce exhaust emissions, and the rounded corners at the inlet of the fuel injection can further improve the flow coefficient of the fuel. With the continuous improvement of the size, shape and accuracy requirements of the inverted taper hole, the difficulty of ...

AI Technical Summary

Problems solved by technology

Electrode deflection mechanism or forming electrode is required to obtain inverted taper hole by micro EDM. Although the forming efficiency is high, the loss of tool electrode is unavoidable, which affects the shape accuracy of the hole, and it is impossible to realize the micro hole on non-metallic materials. processing

Although abrasive flow extrusion grinding can help reduce surface roughness and improve surface quality, abrasive flow will destroy the shape accuracy of the hole, and it is difficult to clean the remaining abrasive particles in the hole

[0004] The patent publication number is CN201110144408.2, which discloses a method and device for electrolytic machining of micro-inverted cone holes. The process is to drill or EDM a through hole on the workpiece in advance, and then electrolytically process the inverse cone on the basis of the through hole. hole, the secondary centering error between the tool electrode and the through hole in the electrolysis process is relatively large, and the centering accuracy directly affects the shape accuracy of the fine inverted taper hole, and because secondary processing is required, the process is also complicated and the technical requirements are high , the machining accuracy is difficult to be well guaranteed

[0005] Laser processing has developed rapidly in recent years, constantly showing advantages that traditional processing cannot match, with outstanding features, such as CO 2 Laser and Nd:YAG laser process micro-holes without tool loss, but their surface quality is poor

Although the development of femtosecond pulsed laser processing has the potential to improve processing efficiency and surface quality, its application is not yet widespread

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