Experimental and numerical investigation on short pulsed laser welding of stainless steel foils

Abstract

Today, there is a miniaturization trend in ultra-precision laser micro-welding applications. It is due to industrial products or components are being made smaller to save space or reduce energy consumptions. For example, laser hermetic sealing of implantable devices, microwave enclosures, batteries, sensors, etc. Since these devices are generally heat-sensitive, a proper control of energy input is necessary in order to avoid any heat damage. Laser micro-welding by pulsed laser systems becomes a main option due to its advantages in precisely managing laser energy in a given time period. In this work, a nanosecond pulsed fibre laser system was used for welding 304 stainless steel thin sheets. The welding efficiency and weld quality were systematically investigated by varying process parameters, such as scanning speed, laser power, pulse width and frequency. In addition, numerical analysis was undertaken to compare with the experimental results. Results show that an effective weld was able to be achieved with a nanosecond pulsed fibre laser system.Today, there is a miniaturization trend in ultra-precision laser micro-welding applications. It is due to industrial products or components are being made smaller to save space or reduce energy consumptions. For example, laser hermetic sealing of implantable devices, microwave enclosures, batteries, sensors, etc. Since these devices are generally heat-sensitive, a proper control of energy input is necessary in order to avoid any heat damage. Laser micro-welding by pulsed laser systems becomes a main option due to its advantages in precisely managing laser energy in a given time period. In this work, a nanosecond pulsed fibre laser system was used for welding 304 stainless steel thin sheets. The welding efficiency and weld quality were systematically investigated by varying process parameters, such as scanning speed, laser power, pulse width and frequency. In addition, numerical analysis was undertaken to compare with the experimental results. Results show that an effective weld was able to be achieved wit...