Investigation of Determination of Laser Welding Conditions for Prediction of Penetration Depths Using Hablanian Plot

Abstract

In order to establish a method to precisely predict penetration depths for macro and micro laser welding at manufacturing sites, we have investigated how to determine experimental conditions for Hablanian plot. We need to obtain three approximate curves (standard approximate curve, error approximate curve, and coefficient approximate curve) for an accurate prediction of penetration depths. We have discussed how to obtain three approximate curves using laser welding data by the use of the fiber laser. As a result, the following findings could be derived. (1) Cubic polynomial is probable as one of the candidates of a function for three approximate curves. (2) A focusing lens used and a spot diameter should be first determined. Second, laser welding experiments should be carried out with changing Log₁₀(Vd/K) and P at regular intervals. (3) Prediction errors can be respectively reduced down to ∼0.06 and ∼0.03 for macro and micro welding above a penetration depth of 4 mm and 0.4 mm.