Fatigue Crack Growth Mechanisms in High Pressure Die-Cast Magnesium Alloys

El Kadiri, H., Horstemeyer, M., Jordon, J. B., & Xue, Y. (2008). Fatigue Crack Growth Mechanisms in High Pressure Die-Cast Magnesium Alloys. Metallurgical and Materials Transactions A. Springer Boston. 39(1), 190-205.

Microstructure-affected micromechanisms of fatigue crack growth operating near the limit plasticity regime were experimentally identified for the four main commercial high pressure die-cast magnesium alloys: AM50, AM60, AZ91, and AE44. These fatigue micromechanisms manifested by the concomitant effects of casting pores, interdendritic Al-rich solid solution layer,  phase particles, Mn-rich inclusions, rare earth-rich intermetallics, dendrite cell size and surface segregation phenomena. These concomitant mechanisms clearly delineated the fatigue durability observed for the AM50, AM60, AZ91 and AE44 Mg alloys in both the low and high cycle fatigue regimes.