Laser drilling of non-circular apertures

• Main Authors: KELLEY, JAMES GEORGE, ROCKSTROH, TODD JAY, CROW, JOHN MAYNARD
• Format: Patent
• Language: English; French; German
• Published: 05.12.2001
• Edition: 7
• Subjects: AIR INTAKES FOR JET-PROPULSION PLANTS; BLASTING; CLADDING OR PLATING BY SOLDERING OR WELDING; COMBUSTION ENGINES; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; GAS-TURBINE PLANTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MACHINE TOOLS; MECHANICAL ENGINEERING; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WEAPONS; WELDING; WORKING BY LASER BEAM

Forming an aperture in a metal wall, including a diffuser opening up and out from bottom, comprises: (i) machining the wall with a laser beam of pulse rate and power sufficient to vaporise the metal; (ii) firing the laser at an acute angle across the surface at increasing pulse rate so that each beam pulse vaporises the metal at a laser spot and drills continuously the metal wall; and (iii) traversing the laser beam latitudinally and longitudinally at increasing speed so that successive spots overlap in decreasing amounts to etch the metal, forming a continuous trench below surface.