Basic Study on Laser Forming (2nd Report)

Abstract

Laser forming of a sheet metal is the bending process caused by the thermal stresses which is produced in the sheet by laser irradiation. Therefore, the temperature distribution in the sheet irradiated with laser beam is one of important factors to determine the bending angle of the sheet. In this study, the influence of temperature distribution and the experimental conditions like the diameter of laser beam and the thickness of a sheet on the bending angle is investigated experimentally. The temperatures of a surface irradiated with CO₂ laser and its opposite surface are measured using an infrared radiation pyrometer with an optical fiber. As a result, the bending angle is directly proportional to the temperature Ts at the sheet surface irradiated with laser beam and the beam diameter D, and inversely proportional to the thickness h of the sheet. A parameter indicated by D^1.41Ts^1.5/h^1.7 has high correlation with the all bending angles obtained under various experimental conditions.