Properties of Steel Welded with CO_2 Laser

摘要

This paper discusses the effect of selected parameters of laser welding on the mechanical properties of welds. Two parameters were analysed: the welding speed and the laser power. The properties of the material in the fusion zone and the heat-affected zone were determined by performing static tensile tests, hardness tests and microscopic analysis. The welding was carried out using a CO_2 laser (wavelength λ = 10.6 um). The specimens were 0.8 mm in thickness, and they were made of DC04 steel. The results indicate that welds produced at different welding parameters have similar mechanical properties. The experiment was conducted and analysed according to requirements of the design of experiment methodology. Laser beam welding allows us to join various dissimilar metals, which have not been possible with conventional methods. It should be emphasized; however, that not all metals are suitable for laser welding; it all depends on their thermal and structural properties. For example, tin, aluminium, lead, tantalum and tungsten are generally difficult to weld.