Surface reaction analysis by X-ray photoelectron spectroscopy using synchrotron radiation and microstructure analysis of AlN layer produced by In-situ direct nitriding process

摘要

In-Situ direct nitriding process to produce AIN in aluminum alloy powder by utilizing the reaction between aluminum and nitrogen gas at temperatures below 823K has been developed. Topmost-surface analysis by X-ray Photoelectron Spectroscopy usingSynchrotron Radiation (SR-XPS) was conducted and chemical bonding changes on aluminum powder surface during heating were investigated. Deoxidization of aluminum oxide (A1{sub}2O{sub}3) surface film by Mg contented in the powders occurred over 670K andA1{sub}2O{sub}3 film was deoxidized and reduced. After the deoxidization of Al{sub}2O{sub}3 surface film, aluminum in powder reacted with nitrogen gas and AlN layer was produced upon the powder surface. In-Situ reacted AlN had a good bonding with aluminum matrix and showed a laminar structure with a layer thickness of 20-30nm. The content of reacted AlN strongly depends on a period of heating in nitrogen gas and on surface area of raw powder.