Microstructure analysis of magnesium alloy melted by laser irradiation

• Published in: Applied surface science 2005-12, Vol.252 (5), p.1723-1731
• Main Authors: Liu, S.Y., Hu, J.D., Yang, Y., Guo, Z.X., Wang, H.Y.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Laser surface melting; Magnesium alloy; Nd:YAG pulsed laser; Numerical simulation; Physics
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2005.03.110

The effects of laser surface melting (LSM) on microstructure of magnesium alloy containing Al8.57%, Zn 0.68%, Mn0.15%, Ce0.52% were investigated. In the present work, a pulsed Nd:YAG laser was used to melt and rapidly solidify the surface of the magnesium alloy with the objective of changing microstructure and improving the corrosion resistance. The results indicate that laser-melted layer contains the finer dendrites and behaviors good resistance corrosion compared with the untreated layer. Furthermore, the absorption coefficient of the magnesium alloy has been estimated according to the numeral simulation of the thermal conditions. The formation process of fine microstructure in melted layers was investigated based on the experimental observation and the theoretical analysis. Some simulation results such as the re-solidification velocities are obtained. The phase constitutions of the melted layers determined by X-ray diffraction were β-Mg 17Al 12 and α-Mg as well as some phases unidentified.