Experimental investigation into laser-based processing of basalt chip stone

Abstract

Basalt is a promising rock variant due to its potential in space-biomining, impact cratering, and developing drilling tools. It finds importance in developing Basalt-based composites and polymers for automobile and defense applications as well. Processing it through conventional processes is strenuous due to its high hardness, frictional, and corrosion resistance. Laser processing provides various advantages and emerges as a potential solution. Current work analyses Basalt chip stone for laser cutting and scanning operations with 2.5 kW and 100 W CO₂ laser. 100 W laser was employed to counter the technical constraint posed by the 2.5 kW laser. Laser cutting and scanning operations for the Basalt sample demonstrate distinct stages of material transition. For laser cutting, a cutting width of 0.12–0.69 mm was obtained for repeated laser cuts of 1~10. For repeated laser scanning, a beam penetration depth of 1.7–8.8 mm and modified specific energy of 30–48.22 kJ/g is obtained for scan repetition from 1~15. Laser scanning emerges as a better material removal choice for the Basalt chip stone sample, though no cracking pattern was observed in the morphology. The microstructure of lased portions displays pulverized debris, propagating cracks, and lava-like formations in comparison to the non-lased portion, which demonstrated crystal patterns with linear, narrow cracks.