Water Jet Guided Laser vs. Conventional Laser: Experimental Comparison of Surface Integrity for Different Aerospace Alloys

Laser cutting is a widely used manufacturing technology in aerospace industry. However, although considered a fast process, lasers have some quality issues associated with high heat input to the materials. Water jet guided laser is a technology that overcomes most of these issues, where pressurized water in the process provides focusing, cooling and cleaning on the cut region, eliminating undesired side effects of the laser. In this study, cutting performances of a water jet guided laser system and a conventional laser system were compared. For this purpose, well-known quality problems of laser cutting were considered, namely dross/burr formation, surface quality, taper and recast layer. The samples were chosen among commonly used aerospace alloys: Haynes 188, Inconel 718, Inconel 625, Rene 41 and Ti-6Al-4V. Visual checks and measurements of surface roughness, taper and recast layer were conducted on the samples. The results show that cutting with a water jet guided laser system overall provides better surface integrity when compared to a conventional laser system.