Laser Surface Modification of AZ91D Magnesium Alloy with Si Powders
(0) To improve the hardness of the AZ91D magnesium alloy, Si powders were preplaced on the surface of AZ91D magnesium alloy and then treated by a high power continuous wave CO2 laser. Mg2Si reinforced Mg-based metal matrix composite have been synthesized. The microstructures and the phases formed in laser surface modified zone were investigated by means of optical microscope (OM), scanning electron microscopy (SEM), electron probe X-ray micro-analyzer (EPMA), and X-ray diffraction as well as Vickers microhardness tester. X-ray diffractometry (XRD) confirmed that the main phases in the alloyed layer to be alpha-Mg, A112Mgl7, and Mg2Si. Mg2Si intermetallic phases are distributed with dendrite shape. The morphology of Al-Mn phase changes from rod-like clusters in AZ91D substrate to global particles in modified layer. The microhardness increased from 80 HV for as-received magnesium alloy to more than 324 HV for laser treated sample can be explained by combining dispersion strengthening of the Mg2Si and grain refining strengthening of Mg 17A112.
Magnesium alloy Intermetallic Laser surface modification Microstructure
ZHANG Jian-bin JI Gen-shun FAN Ding
State Key Lab.of Gansu Advanced Non-ferrous Metal Materials,Lanzhou University of Technology,Lanzhou 730050,China
国际会议
The Fourth Asian Conference on Heat Treatment and Surface Engineering(第四届亚洲热处理及表面工程大会)
北京
英文
569-573
2009-10-27（万方平台首次上网日期，不代表论文的发表时间）