Two types of joints have been studied: butt joint and lap (“transparency”) joint (pictures of figures 1a to 1d).The
welding trials have been performed with two types of high power lasers: Nd:YAG and CO2 lasers.The study has
been performed first on rectangular samples -300 mm x 150 mm- (Figure 2a); from these samples the different
metallographic and mechanical samples have been obtained. Two thicknesses have been used for the study: 2 mm
and 5 mm.