Hybrid Laser Machining Multi-Material Stack-Ups

The drilling process is divided into multiple sequential stages with decreasing pulse energies. The first stage uses high energy to create the initial hole through all layers, subsequent stages use progressively lower energies to clean up burrs and repair tear-out, and the final stage uses very low energy for precision sizing. This segmentation of the drilling process into distinct energy levels resolves the contradiction by addressing both alignment and surface quality in a single integrated operation.

The system employs periodic pulsed laser drilling with varying pulse energies rather than continuous drilling. Multiple pulses are delivered in sequences with different energy levels - high energy pulses for material removal and low energy pulses for surface finishing. This periodic action with varying parameters allows the same laser to perform both rough drilling and finishing operations, eliminating burrs and tear-out while maintaining alignment.

The patent merges multiple drilling operations into a single integrated process. Instead of drilling each layer separately and then assembling, the laser drills through all layers simultaneously in one operation while they remain assembled. This merging of operations maintains layer integrity through proper pulse energy selection while achieving superior hole alignment and positioning accuracy that cannot be obtained through separate drilling operations.

The system changes laser pulse energy parameters dynamically during the drilling process. High energy parameters are used initially for penetrating through all layers, then parameters are adjusted to lower energies for cleaning and finishing. This parameter change strategy allows the process to maintain layer integrity while achieving precise hole alignment by adapting energy levels to different stages of the same continuous operation.

The laser drilling process maintains continuous useful action by performing multiple functions in one uninterrupted operation. The same laser beam continuously drills through layers, cleans burrs, repairs tear-out, and sizes holes without stopping for assembly-disassembly cycles. This continuity eliminates idle time and redundant handling operations, achieving high hole quality while maintaining high productivity.

The pulsed laser drilling system performs multiple functions universally - it drills holes, removes burrs, repairs tear-out, and sizes features all in one operation. This multi-functionality eliminates the need for separate finishing processes and assembly-disassembly cycles, achieving both high hole quality and high production efficiency simultaneously.

The laser pulse sequence is segmented into different energy levels. High energy pulses are used sparingly for initial material removal to maintain machining speed, followed by multiple lower energy pulses that clean up surface damage and prevent melt accumulation. This segmentation allows the system to achieve both high productivity and clean surfaces by optimizing energy distribution across the pulse sequence.

The system converts the potentially harmful effect of high energy pulses creating surface damage into a benefit by immediately following with lower energy pulses that clean and repair the damage. The initial high energy pulses create controlled damage that is then systematically removed by subsequent pulses, turning what would be a defect into an opportunity for precise surface finishing within the same continuous process.