Microstructure and damage evolution during tensile loading in a wrought magnesium alloy
This paper describes an investigation of microstructure and damage evolution in a tensile specimen of a AZ61 magnesium alloy. The evolution of the properties is capture through a stereological analysis of interrupted uniaxial tensile test specimens. The analysis identified second phase particles, separated the oxide/intermetallics from Mn-Al and Mg-Al phase particles, and quantified the number of cracked particles. The number density and area fraction of these cracked Mn-Al and Mg-Al particles is shown as a function of strain and compared to the Horstemeyer-Gokhale  damage nucleation model.
Four conclusions are drawn from the results. (1) The area fraction of cracked Mn-Al and Mg-Al particles varies exponentially with strain under uniaxial tension. (2) The number density of cracks follows a shallow nonlinear pattern. (3) Three separate particle types were observed in the Mg alloy specimens: oxide/intermetallics, Mn-Al, and Mg-Al phases. (4) Cracks were observed in the Mn-Al and Mg-Al based particles.
- ↑ M.F. Horstemeyer, A.M. Gokhale, Int. J. Solids Struct. 36 (1999) 5029. http://www.sciencedirect.com/science/article/pii/S002076839800239X