Multi-objective Process Optimization of Pulsed CO2 Laser-TIG Arc Hybrid Lap Welding of Magnesium Alloy AZ31B

• Main Authors: Ming-hong Lin, 林銘宏
• Other Authors: Yih-fong Tzeng
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/cxyr7t

碩士 === 國立高雄第一科技大學 === 機械與自動化工程所 === 96 === As the advancement of technology, the quality of human life continues to improve significantly. Additionally, the so-called BRICs are growing up very fast in their economies. These factors make the low-weight and high-strength metals play a more and more important role in the industry, particularly the magnesium alloy. Because of its good plasticity, easy processing, high damping and good electromagnetic shielding effects, it has been widely applied in automobiles, aeronautics, and 3C product industries. The magnesium alloy with a high reflectivity to CO2 laser makes it difficult to weld effectively. But when CO2 laser is coupled with TIG arc, this problem can be easily resolved although the later produces wider welds. It is because that TIG arc enables the enhancement of magnesium’s absorptivity to the laser beam, leading to better penetration and higher welding speed. So the study tries to utilize pulsed CO2 laser coupled with TIG arc to lap weld magnesium alloy where laser beam welding is the main process assisted by TIG arc. Firstly, a series of laser welding experiments are to be carried out under the same output power for a systematic investigation of the effects of process parameters on the aspect ratio and the micro-hardness of the welds. Finally, the study employs Taguchi methods coupled with principal component analysis, Fuzzy-based Taguchi-PCA and RSM (Response Surface Methodology)-based Taguchi-PCA to develop the multiple quality characteristics process optimization of pulsed CO2 laser-TIG arc hybrid lap welding of magnesium alloy AZ31B.