The Physics Society of Iran Iranian Journal of Physics Research 1682-6957 14 3 2019 11 26 Influence of shielding gas composition on weld profile in pulsed Nd:YAG laser welding of low carbon steel Influence of shielding gas composition on weld profile in pulsed Nd:YAG laser welding of low carbon steel 41 46 1086 FA M Jokar F MalekGhaini M J Torkamany M Sheikhi Journal Article 2019 11 26 Weld area and weld depth/width ratio can be considered to be of the most important geometrical factors in pulsed laser welding. The effects of carbon dioxide and oxygen additions to the argon shielding gas on the weld properties in pulsed laser welding of low carbon steel is investigated. Presence of carbon dioxide and oxygen up to 10 and 15 percent respectively decreases the weld geometrical factors. But, at higher levels of additions, the weld geometrical factors will increase. It is observed that the plasma plume temperature decreases from 6000K to 5500K with the addition of 15% carbon dioxide but increases to 7700K with 25% carbon dioxide addition. Increase in laser absorption coefficient, laser energy absorption, formation of oxide layer on the work-piece surface, exothermic reactions and their competitive effects can be considered as the competing phenomena involved in such a behavior in the weld profile Weld area and weld depth/width ratio can be considered to be of the most important geometrical factors in pulsed laser welding. The effects of carbon dioxide and oxygen additions to the argon shielding gas on the weld properties in pulsed laser welding of low carbon steel is investigated. Presence of carbon dioxide and oxygen up to 10 and 15 percent respectively decreases the weld geometrical factors. But, at higher levels of additions, the weld geometrical factors will increase. It is observed that the plasma plume temperature decreases from 6000K to 5500K with the addition of 15% carbon dioxide but increases to 7700K with 25% carbon dioxide addition. Increase in laser absorption coefficient, laser energy absorption, formation of oxide layer on the work-piece surface, exothermic reactions and their competitive effects can be considered as the competing phenomena involved in such a behavior in the weld profile https://ijpr.iut.ac.ir/article_1086_d91d1b4d82419de8a614abce9cc0e6d4.pdf