The effect of spot size and laser beam quality on welding performance when using high-power continuous wave solid-state lasers

Abstract

For welding, cutting and surface engineering applications, the use of high-power fibre-delivered beams from solid-state lasers offers many advantages. Only 10 years ago, the only available laser source of this type was a lamp-pumped Nd:YAG laser, a laser with modest beam quality. Notwithstanding this modest beam quality, these laser sources have been widely adopted for welding applications, particularly in the automotive industry. Today however, the range of fibre-delivered continuous wave (CW) laser beams has increased significantly, as has the available laser beam quality. The choice of laser source for a particular application is no longer obvious. This paper addresses the issue of how the laser beam quality of CW fibre-delivered lasers affects welding performance, by comparing a series of welds made in thin and thick section aluminium and steel, using a constant laser power from laser sources with different beam qualities.For welding, cutting and surface engineering applications, the use of high-power fibre-delivered beams from solid-state lasers offers many advantages. Only 10 years ago, the only available laser source of this type was a lamp-pumped Nd:YAG laser, a laser with modest beam quality. Notwithstanding this modest beam quality, these laser sources have been widely adopted for welding applications, particularly in the automotive industry. Today however, the range of fibre-delivered continuous wave (CW) laser beams has increased significantly, as has the available laser beam quality. The choice of laser source for a particular application is no longer obvious. This paper addresses the issue of how the laser beam quality of CW fibre-delivered lasers affects welding performance, by comparing a series of welds made in thin and thick section aluminium and steel, using a constant laser power from laser sources with different beam qualities.