Tensile deformation behavior of as-extruded MB350 magnesium alloy at elevated temperature

Abstract:

The tensile tests and microstructure evolution of as-extruded Mg-3Al-3Zn-1Ti-0.6RE magnesium alloy at elevated temperature were conducted on WDW3100 microcomputer control electron universal testing machine and Zeiss microscope at strain rates ranging from 10-4 s-1-10-2s-1 and deformation temperature of 623K-723K. The result has shown that temperature and strain rate are the important factors influencing the rheological stress. During the process of deformation, the flow stress decreases with the increase of temperature and the decrease of strain rate. Under this experimental condition, the deformation constitutive equation of the alloy can be described by hyperbolic sine function.Among them, the stress exponent and the activation energy of the as-extrude alloy are 3.286 and 238KJ/mol. The most important deformation mechanism of this alloy is dislocation slip and climb.

Key words:as-extruded Mg-3Al-3Zn-1Ti-0.6RE magnesium alloy; elevated temperature tensile; flow stress; constitutive equation; microstructure