The morphology and texture of zinc coatings deposited on interstitial free (IF) steel sheets were investigated by means of scanning electron microscopy (SEM) and orientation distribution function. It was shown that the microstructure of the coatings consisted of thin hexagonal platelets tilted with respect to the substrate surface. Zinc coatings exhibited low angle pyramidal { 11.5}nonfiber texture component resulting from epitaxial growth via two-dimensional (2D) nucleation. The 2D nucleation was attributed to severe zinc hydroxide adsorption on the substrate surface during the nucleation stage,which can inhibit three-dimensional (3D)nucleation and promote nonfiber texture. The pyramidal texture was beneficial for plastic deformation of zinc coatings because a significant amount of resolved shear stress can be obtained when the uniaxial stress is applied.%采用高速电镀技术在无间隙原子钢(IF钢)基板上镀锌,借助扫描电镜和取向分布函数研究镀锌层的微观形貌和织构.结果表明,镀锌层由一系列倾斜于基体表面紧密排列的六方形片晶组成,初始电沉积时基体表面氢氧化锌的大量吸附抑制锌的三维形核,二维晶核的外延生长以及IF钢基板的{111}纤维织构促进镀锌层{11.5}锥形非纤维织构的形成.镀锌层呈锥形织构时,片晶的滑移面与基体表面呈一定角度,保证镀层在受到轴向应力时产生一定量的分切应力,从而有利于自身的塑性变形.
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