Abstract
Abstract High power density laser was applied during rock breaking for sandstone with different laser parameters. The fracture morphologies and quantitative characterization as well as the parameters on specific energy and rate of perforation were analyzed. It was found that a complex crack net structure was formed and the cracks area and length on the surface of sandstone specimen almost increased linearly with the number of laser perforation. Furthermore, the diameter and depth of laser perforation, the maximum width of cracks, the maximum depth and total circumferential length of side cracks increased with laser power and laser irradiation time. The experimental results demonstrated that the SE values gradually decreased with laser power while the ROP values increased. However, the SE values of sandstone by laser perforation presented a trend of first increase and then decrease, while the ROP values decreased gradually with laser irradiation time. A smooth glaze layer was formed on the inner wall of the laser perforation, where there also was plenty of shrinkage hole. Obvious cracks were generated and propagated along the inner wall. Typical brittle fracture occurred with the mix fracture mechanisms of intergranular fracture and transgranular fracture.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call