中文摘要：

通过直流电沉积技术制备具有高密度纳米孪晶结构的Ni，并对该材料中存在的五次孪晶结构进行了深入系统的电子显微分析．获得了纳米孪晶Ni中五次孪晶结构的HRTEM图像和SAED花样；研究了单个晶粒内部五次孪晶的结构特性、分布规律．结果表明，五次孪晶是由5个{111｝晶体旋转组成，五次旋转孪晶产生的7．35°本征间隙至少由五次孪晶中的2个孪晶界分担；而且分担间隙的孪晶界呈现宽化现象，并且分解为新的孪晶，导致五次孪晶晶粒在整体形状上不具有五次对称性，呈现出一定的不规则形状．TEM截面形貌分析表明，电沉积纳米孪晶Ni呈现{110}面平行样品表面织构，晶粒为柱状晶分布，柱状生长方向为[110]．通过综合结构表征，给出了五次孪晶在三维空间的结构模型．

英文摘要：

The nanocrystalline Ni thin films with high density nano-scale growth twins were synthesized by direct electrodeposition technology. The five-fold twinning structure in electrodeposited nano-twin Ni was systematically investigated by TEM. The remarkable diffraction pattern and HRTEM images obtained from the cross-section observation demonstrate directly that the electrodeposited nano-twin Ni has five-fold twinning structure with five { 111 } twinned subcrystals and systematically analyzed the 7.35° intrinsic structural gap. In this work, the 7.35° gap was at least inset in two twin boundaries of the five-fold twin, the twin boundaries which share the 7.35° gap always broaden and was decomposed into other twins, so that, the grain present a irregular shape, cross-sectional TEM micrograph revealed that the electrodeposited nano-twin Ni had columnar grain structure with a strong { 110} texture. By means of comprehensive structure characterization, a new space structural model of the five-fold twin was proposed.