Microstructure and mechanical properties of hot extruded tube of AZ80 magnesium alloy

Extrusion technology of magnesium alloy AZ80 tube was studied.The microstructure and mechanical properties of extruded tube of the alloy were analyzed.The results show that the material grain size is refined by hot extrusion,and the mechanical properties are increased.The grain size of the alloy tube is changed from 28 μm as casting to 4 μm as extruded.Tensile strength is changed from 162 MPa to 265 MPa,and yield strength is from 74 MPa to 180 MPa,and elongation is from 4% to 14%.With the increasing of extrusion ratio,the grain size is refined significantly and the elongation and yield strength are increased.The suitable extrusion parameters of the alloy tube are that extrusion ratio is 18.2,forming temperature is 390 ℃,die preheating temperature is 360 ℃,conical semi-angle of fovea die is 60°-70°,and extrusion speed is 1 mm/s.