为了更清楚地认识颗粒增强铝塑性差的细微观机制,进行了(A12O3)p/6061Al的拉伸和三点弯曲变形实验,并用扫描电镜观察了变形与断裂的细微观特征.发现:(1)在加载过程中,总是基体先发生变形局部化,形成变形带;变形带内较大的A12O3颗粒优先开裂,形成颗粒尺度的微裂纹;变形带内的集中变形和Al2O3颗粒的继续开裂交互作用,导致微裂纹沿着变形带连接与扩展进而发生宏观低塑性断裂;(2)加载方式、材料状态和变形温度对上述过程没有本质影响.根据以上观察结果和颗粒增强铝的强化机理,讨论了塑性差的细微观机制以及材料状态和变形温度对(Al2O3)p/6061Al塑性的影响.
参考文献
| [1] | Lloyd D J. Particle reinforced aluminium and magnesium matrixcomposites [J]. Int Mater Rev, 1994,39: 1. |
| [2] | Clyne T W, Withers P J. An Introduction to Metal Matrix Composites [M]. London:Cambridge University Press, 1993. |
| [3] | Liaw P K, Gungor M N. Fundamental Relationships betweenMicrostructures and Properties of Metal Matrix Composites [M].Warrendale PA: The Metallurgical Society of AIME, 1989. |
| [4] | Arsenault R J. Metal Matrix Composites: Mechanisms and Prop-erties [M]. San Diego: Academic Press, 1991. 179. |
| [5] | Everett R K, Arsenault R J. Metals Matrix Composites: Processing and Interfaces [M]. San Diego: Academic Press, 1991. |
| [6] | Zhao D, Tuller F R, Lloyd D J. Fracture at elevated tempera-tures of a particle reinforced composite [J]. Acta Metall Mater,1994,42:2525. |
| [7] | Welpmann K. Recent Advances in Science and Engineering ofLight Metals [M]. Japan Institute of Light Metals, 1991. 281. |
| [8] | Li H X, Lo J, Xiao X R. Strengthening of Al2O3/6061A1 particulate composite at liquid nitrogen temperature [J]. Scripta MetallMater, 1995,33:1423. |
| [9] | 陈立强.低温处理影响颗粒增强铝力学行为的细观力学机制[D].北京:北京航空航天大学,2000. |
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