(1. 北京科技大學(xué) 材料學(xué)院, 北京 100083；
2. 北京廣靈鎂業(yè)公司, 北京 100071)
摘 要: 降低擠壓溫度是細化鎂合金晶粒和提高強度的有效手段, 但對靠析出強化的AZ80鎂合金來說, 降低擠壓溫度會造成擠壓時的析出, 從而影響最終時效的效果。 分析了在工業(yè)生產(chǎn)用擠壓機上380 ℃和330 ℃擠壓出的AZ80鎂合金擠壓和時效的組織和性能。 結(jié)果表明： 330 ℃擠壓可獲得6 μm的均勻等軸晶粒組織, 但冷卻后的樣品中明顯存在析出物, 后續(xù)時效過程較快, 但最高強度不如高溫擠壓樣品的最高強度； 在380 ℃下擠壓并時效后, 其最高抗拉強度可達400 MPa, 延伸率可達8%。 X射線衍射織構(gòu)測定表明, {0002}∥擠壓軸的織構(gòu)對性能的提高也起一定的作用。
關(guān)鍵字: AZ80鎂合金； 變形； 時效處理； 織構(gòu)； 力學(xué)性能
of AZ80 magnesium alloy
（1. School of Materials Science and Engneering, University of Science and
Technology Beijing, Beijing 100083, China;
2. Guangling Magnesium Science and Technology Co. Ltd.,
Beijing 100071, China）
Abstract: Reducing extrusion temperature is the effect way to refine the grain and enhance mechanical properties of magnesium alloys. However, it may also stimulate the precipitation of second phase during extrusion of AZ80 alloy, and therefore reduce the hardening effect. The microstructures and mechanical properties of these two types of AZ80 magnesium alloys extruded at 380 ℃ and 330 ℃, respectively, on a commercial extruding machine were analyzed. The results indicate that the microstructure with grain size of 6 μm is obtained at the extrusion temperature of 330 ℃. However, the second phase is precipitated along the grain boundaries during deformation which influence subsequent microstructure evolution and properties. Ultimate tensile strength over 400 MPa with an elongation of 8% is achieved after aging treatment of the 380 ℃ extruded samples. The strong extrusion texture of {0002} is determined and regarded to be responsible mainly for the high properties compared with the grain refinement and precipitation.
Key words: AZ80 magnesium alloy; deformation; aging treatment; texture; mechanical properties
