Microstructural Characterization of the Reaction Product Region Formed Due to the High Temperature Interaction of ZnO[0001] Single Crystal with Liquid Aluminum

Archives of Metallurgy and Materials

N. Sobczak¹  R. Nowak¹  J. Wojewoda-Budka²  K. Stan² 

[1] Centre for High Temperature Studies, Foundry Research Institute, 73 Zakopianska st., 30-418 Kraków, Poland;Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta st., 30-059 Kraków, Poland

关键词: Keywords : Al/ZnO interface;    in situ composites;    redox reaction;    α-Al2O3;    δ-Al2O3;    γ-Al2O3;   

DOI  :  10.2478/v10172-012-0197-y

学科分类：金属与冶金

来源: Akademia Gorniczo-Hutnicza im. Stanislawa Staszica / University of Mining and Metallurgy

【 摘 要 】

The study was focused on the microstructure characterization at the micro- and nano scale of the reaction product region (RPR) formed due to the interaction between the liquid aluminum and ZnOSC[0001] single crystalline substrate at 1000ºC. The research was carried out on the Al/ZnO couple produced by the sessile drop method under vacuum within two different procedures: 1) classical contact heating and cooling; 2) pushing drop procedure allowing opening the Al/ZnO interface at the test temperature and, therefore, prevent influence of cooling with Al drop on interface structure. The microstructure observations of the sample after using classical contact heating procedure revealed the formation of the RPR of ∽50 μm in thickness extending into the ZnOSC single crystal substrate. It was composed of the ceramic α-Al2O3 and metallic Al(Zn) mutually interpenetrating lattices, typical for the C4 type structure. Additionally, at the ZnO/RPR interface, the presence of a thin (∽250 nm) layer of the metastable δ-Al2O3was detected. The obtained results were compared with experimental data found for the sample after pushing drop procedure resulting in the formation of two layers of ZnAl2O4 spinel and alumina, exhibiting strong epitaxial growth. The selected area diffraction patterns clearly evidenced that the crystal structure of formed Al2O3 corresponds to the tetragonal δ-phase.

【 授权许可】

Unknown