Study On Hot Extrusion In Complex Variable Angle Of Magnesium Alloy

Magnesium alloy is the lightest metal structural materials in practical applications,has both a high specific strength and stiffness and fatigue strength, also has good electrical conductivity, thermal conductivity and magnetic shielding. It is one of the ideal structural materials which is used to achieve lightweight equipment. The method of extrusion processing to product magnesium profiles has advantage of saving metal and high production efficiency. In the extrusion process, the interior mold is sealed. So it is difficult to control the material flowing, the stress field, the strain field and the loading condition. At the same time, as the key point, extrusion production of mold design often depends on the experience to modify the mold with the experimental mold to carry on repeatedly and it often creates the waste manpower physical resource. In order to improve the extrusion product quality and enhance the mold rated capacity, Finite Element Analysis is a very useful method.Magnesium alloy extruded angle has a very important role in the extrusion process. It is the main area of magnesium alloy extrusion bar. Magnesium Alloy Extrusion currently focused on the extrusion ratio and few studies in this area, this paper uses finite element simulation software DEFORM to carry out the AZ31 magnesium extrusion process simulation, for confirming the effect of optimized extrusion mold. It research the effects of complex variable angle on mechanical properties and the quality of AZ31 magnesium alloy surface.1、 Extrusion die angle often become pressing plate or die as one in conventional extrusion die. The molds will squeeze horn split out as a central module replacement, to achieve a big change for a small mold die without thinking, so that the extrusion experiments can more easily experiment with different mold structures. In industrial production can also increase productivity, material savings and reduce production costs.2、The new mold structure can effectively improve the dead zone, reducing extrusion load, speed up the flow rate of the outer layer of the metal, making the metal more uniform organization, to improve the properties of the metal.3、Replace central die cone angle of magnesium alloys during extrusion speed and temperature has a significant impact. Cone angle increases, the extrusion speed in the bar surface with the core of the difference, the lower the temperature during extrusion. And then extruded bar stock and better surface quality.4、The experimental results show that when the extrusion speed equal to 5mm/s, with cone angle of 60° for the central module can be replaced by a smooth magnesium alloy bars.5、Design of composite multiple ladder displacement angle, the material during the extrusion process by repeatedly squeezed, strained material is gradually increased in the outer layer being greater than the weight of a ladder shear strain, increasing the number of materials can effectively ladder improve the material equivalent strain, the magnesium alloy greater deformation strengthening.6、In the same number of steps extruded composite variable angle, variable angle selected composite cone angle increases, the metal helps squeeze liquidity, so that multiple ladder can squeeze better results.