Papers by Keyword: Magnesium Alloy Tube

Abstract: The microstrctural evolution pre and post heat treatment is critical to achieve a successful product for metal forming process. This paper aims to investigate the microstructual effect of the magnesium alloy tubes undergone various heat treatment conditions to achieve material homogenization. The heat treatment conditions under various periods of time (1, 2, 6, 12 and 30 hours) at 400 °C were employed to investigate the microstructural effect on hydroforming magnesium tubes. The greatly reduced impurity embedded in grain boundaries and more uniform grain sizes do indicate the improvement of material strength and ductility. To validate the conclusion, corresponding tensile tests at the different temperatures (20 °C and 200 °C) were carried out. The increased engineering strain in two directions (hoop and longitudinal) implies that the microstructural evolution is unquestionably useful to enhance the ductility of the magnesium tubes. Subsequently, the tubes after optimal heat treatment condition at 400 °C for 6 hours were used to further carry out the thermal hydroforming process for validation. The defect-free hydroformed tubes were produced under the same working condition, which is unable to be achieved for tubes without the heat-treatment process.

Abstract: The AZ31 magnesium alloy tube was used for electromagnetic forming experiment of three kinds of input voltages. The stress-strain state of tube forming was analyzed. It was shown that the cause of oblique crack of tube was of axial inhomogeneous distribution and , and the cause of longitudinal crack was and of inhomogeneous distribution in circumferential direction. Moreover, the electromagnetic field and force field during electromagnetic forming was simulated by ANSYS software. The experiment proved the simulation result.

Abstract: A new maching method of pretreatment magnesium alloy surface was design based on abrasive belt grinding technology, which offered a kind of technology for magnesium alloy tube surface machining. Experimental results indicated that abrasive grain granularity, belt speed and workpiece feed speed play an important role in grinding for magnesium alloy tube surface, which made magnesium alloy tube surface roughness from 0.22 um to 2.93 um with 400 grade to 80 grade on abrasive grain granularity of belt, raise the belt speed to reduce surface roughness, but raise workpiece feed speed to deteriorate roughness.