十次准晶中层错位错和小角晶界的透射电镜研究

十次准晶中层错位错和小角晶界的透射电镜研究 TEM INVESTIGATION OF STACKING FAULTS,DISLOCATIONS AND SMALL-ANGLE GRAIN BOUNDARIES IN DECAGONAL QUASICRYSTAL 王仁卉 Wang Renhui Yah Yanfa Dai Mingxing 1 first-author 鄢炎发 1 戴明星 1 武汉大学物理学系材料物理研究室 武汉大学物理学系材料物理研究室 Laboratory of Material Physics,Department of Physics,Wuhan University Laboratory of Material Physics,Department of Physics,Wuhan University 在 A 1 70 Cc N i（5）十次准晶中首次观察到三种类型层错,其中第一和第二类层错面垂直和平行于十次轴,其位移矢量 R 都在层错面内,且沿准周期方向。第三类层错是位移矢量不在层错面内的平移畴壁。用会聚束电子衍射方法首次测定了十次准晶中位错的 Burgers矢 b 的模,观察到 b=[3/4,0,0,0,0,0],b=[1,0,0,0,0,0] 的螺位错和 b=[1/2,0,0,0,0,0]的刃位错,且不少位错以同号平行位错对的形式存在。首次观察到十次准晶的三种小角晶界,即由刃位错壁构成的倾斜晶界,由螺位错壁构成的扭转晶界和由位错网络构成的小角晶界。最后探讨了十次准晶形变的微观机制。 In Al 70 Co 15 Ni 15 decagonal guasicrystal （DQC） three types of stacking faults have been observed.The first and second types have their fault-planes respectively parallel and perpendicular to the ten-fold axis.Their displace- ment vectors lie in the fault planes and are along a quasiperiodic direction. The third type of stacking fault is a translation domain boundary with a dis- placement vector which does not lie in the stacking plane.The magnitudes of the Burgers vectors b of dislocations in DQC have been determined at the first time by using convergent beam electron diffraction.Dislocations with b= [1/2,0,0,0,0,0],b=[3/4,0,0,0,0,0] and b=[1 0 0 0 0 0] have been ob- served.Many dislocations in DQG have been observed to be arranged as par- allel disloaction pairs with the same sign of Burgers vectors.Three kinds of small angle grain boundaries （SAGB） in DQC have been observed at the first time,they are tilt boundary consisting of edge dislocation wall,twist bounda- ry consisting of parallel screw dislocation wall and SAGB consisting of dislo- cation network.At last,microscopic mechanism ofdeformation of DQCs have been explored in the present paper. 十次准晶 缺陷 层错 位错 小角晶界 透射电子显微术 O77;O483 国家自然科学基金资助课题 1992-02-01 2021-04-01 2