摘要
目的研究热浸镀铝锌板镀层微观组织结构。方法利用扫描电镜、能谱和电子探针分析铝锌板表面与镀层的组织形貌与成分;利用X射线衍射与电子背散射衍射技术分析铝锌板镀层的物相组成与相结构。结果铝锌板表面为典型的锌花形貌,锌花内部呈现出有条理的枝晶状结构。铝锌板镀层沿厚度方向分为内外两层:外层为合金层,其成分主要为Al、Zn和Si,该层主要是由富Al相、富Zn相以及少量条状高Si相构成;与钢基体接触的内层为过渡层或金属间化合物层,该层的厚度仅约为1μm,其成分为Fe、Al和Si,该层由弥散致密的细颗粒与少量分散的粗颗粒构成。此外还发现,有少量条状或颗粒状的高Si相分布在过渡层与合金层之间。结论铝锌板镀层中合金层的富Al相、富Zn相以及条状高Si相的相结构分别为Al的面心立方结构、Zn的密排六方结构和Si的面心立方结构,高Si相的分布特性可以有效地控制镀层的厚度。过渡层的相结构更倾向于单斜结构的Al13Fe4,该层在形成过程中,部分细颗粒相长大并发生粗化,从而形成粗颗粒相穿插于过渡层与合金层之间,进一步加强了过渡层与合金层的连接,进而间接地对镀层粘附性能和延伸性能的提高起到了关键性的作用。
The work aims to study the microstructure of the hot dip Al-Zn plated coating.Scanning electron microscope,energy spectrum and electron probe are used to analyze the structure and composition of the surface of the aluminum zinc plate and the coating.X-ray diffraction and electron backscatter diffraction are used to analyze the phase composition and phase structure of the Al-Zn plate coating.The surface of the Al-Zn plate is a typical spangle morphology,and the interior of the zinc flower shows a structured dendrite structure.The Al-Zn plate coating is divided into an inner layer and an outer layer along the thickness direction,the outer layer is an alloy layer which is mainly composed of Al,Zn and Si.The layer is mainly composed of Al-rich phase,Zn-rich phase,and a small number of strip-shaped high Si phase.The inner layer in contact with the steel substrate is a intermetallic compound layer.The thickness of this layer is only about 1μm and its composition is Fe,Al and Si which is composed of densely dispersed fine particles and a small amount of dispersed coarse particles.In addition,a small amount of high Si phase in the form of strips or particles was found between the transition layer and the alloy layer. The phasestructures of the Al-rich phase, Zn-rich phase, and strip high Si phase of the alloy layer in the Al-Zn plate coating are Alface-centered cubic structure, Zn close-packed hexagonal structure and Si face-centered cubic structure respectively. Thedistribution characteristics of the high Si phase can effectively control the thickness of coating. The phase structure of thetransition layer is more inclined to the monoclinic Al13Fe4. During the formation of this layer, part of the fine particle phasegrows and coarsens, thereby forming a coarse particle phase, interposed between the transition layer and the alloy layer, whichfurther strengthens the transition layer and the alloy layer. The connection indirectly plays a key role in improving the adhesionand elongation of the coating.
作者
崔桂彬
鞠新华
任群
孟杨
尹立新
CUI Gui-bin;JU Xin-hua;REN Qun;MENG Yang;YIN Li-xin(Shougang Group Company limited Research Institute of Technology,Beijing 100043,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2021年第4期361-368,375,共9页
Surface Technology
作者简介
崔桂彬(1983—),男,硕士,高级工程师,主要研究方向为钢铁材料微观表征。邮箱:107634667@qq.com。
