학술논문
Online determination of the hole depth during drilling with ultrashort laser pulses for depth-adapted drilling strategies
Document Type
Article
Author
Source
In Procedia CIRP 2024 124:649-652
Subject
Language
ISSN
2212-8271
Abstract
Drilling of deep, diffuser-shaped microholes in thick steel plates with ultrashort-pulsed lasers is still a challenge. With constant laser parameters the process parameters change with increasing hole depth leading to stagnation of the drilling depth and requiring depth-adapted strategies to allow efficient drilling. In the present work, optical coherence tomography (OCT) was used for in-situ, time-resolved acquisition of the hole depth during laser drilling with ultrashort laser pulses. The OCT-based measurements were validated by comparing the number of pulses necessary for breakthrough as measured with OCT with the number of pulses measured camera-based to drill through holes in steel plates of various thickness. The online-determination of the drilling progress allowed to apply a depth-adapted drilling strategy in order to drill conically-shaped microholes in steel with a depth of up to 10 mm.