Development of Mg tube using laser welding for bike frame

Abstract

Bicycle is historical device for transportation. Also it is environmental friendly and good for a health. The higher the strength is the better for material of bicycle, because the weight of it is lower and lower. Magnesium alloy have higher potential for bicycle cause its high strength but low density. But magnesium alloy have poor formability at room temperature and hardly welded with conventional welding processes. The laser welding was effective way to joint magnesium alloys because it had high weld strength and productivity compare with other welding processes.In this study, the punch and die set was designed and machined according to the results of FEM simulation. The forming of magnesium sheet with tubular shape was done at elevated temperature. The seam butted both end face of magnesium sheet was welded with laser. The tensile strength of magnesium tube prepared on this study was higher than conventional extrusion tube. Consequently, the bicycle frame was assembled successfully with magnesium alloy tube.Bicycle is historical device for transportation. Also it is environmental friendly and good for a health. The higher the strength is the better for material of bicycle, because the weight of it is lower and lower. Magnesium alloy have higher potential for bicycle cause its high strength but low density. But magnesium alloy have poor formability at room temperature and hardly welded with conventional welding processes. The laser welding was effective way to joint magnesium alloys because it had high weld strength and productivity compare with other welding processes.In this study, the punch and die set was designed and machined according to the results of FEM simulation. The forming of magnesium sheet with tubular shape was done at elevated temperature. The seam butted both end face of magnesium sheet was welded with laser. The tensile strength of magnesium tube prepared on this study was higher than conventional extrusion tube. Consequently, the bicycle frame was assembled successfully with magnesium allo...