摘要
通过原子力显微镜（ＡＦＭ）首次发现和证实了纳米３Ｙ－ＴＺＰ陶瓷（１００ｎｍ左右）室温循环拉伸断口表面的某些微观区域已发生了超塑性变形；而比较亚微米尺寸的３Ｙ－ＴＺＰ陶瓷（３５０ｎｍ）经循环拉伸后，断口表面的晶粒仍保持等轴晶形。说明晶粒尺寸大小是陶瓷室温循环塑性变形的关键。另外借助原子力显微镜（ＡＦＭ）从断口侧面首次观察到大量弯曲的滑移线和表面初始的“挤出”现象，由此引伸出纳米陶瓷裂纹尖端的微区内发生的室温超塑性变形的微观机制为位错的滑移运动所为．
It was first observed that superplastic deformation occurred among the grains at the fatigue fracture surface after cyclic tension at room temperature for a dense 98.5%(T. D.) nanocrystalline 3Y-TZP ceramics (100nm or so) by SEM and AFM. Comparably, the retention of an equiaxed grain shape was observed after Cyclic tension at room temperature for 0.35μm sized 3Y-TZP ceramics. It was proved that the grain she of ceramics was a key of plastic deformation at room temperature. It was also first identified by AFM that curved slip lines and the ' young' extrusion on the side face of fatigue fracture were developed.The local plastic deformation was resulted from the slip motion of dislocation.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
1995年第4期411-416,共6页
Journal of Inorganic Materials
基金
国家自然科学基金
国家攀登计划A纳米材料科学的资助
关键词
纳米陶瓷
氧化锆陶瓷
室温
超塑性变形
循环变形
Y-TZP
nanocrystalline
fatigue fracture surface and side face
superplastic deformation
dislocation
