TMF criteria for Lost Foam Casting aluminum alloys.

ABSTRACT The purpose of this paper is to define a thermo-mechanical fatigue criterion in order to predict the failure of aluminum alloys components issued with the lost foam casting process and used in particular in the automotive industry. The microstructure of the studied materials (A356-A319 aluminum alloys) is clearly affected by the lost foam casting process which can directly affect the mechanical properties, the damage mechanisms and the fatigue failure of specimens and components. The major problem in defining a predictive fatigue criterion in this case is the fact that it should be applicable for the component which is submitted to complex multiaxial thermo-mechanical loadings. Since many years, energy-based criteria have been used to predict fatigue failure of this class of materials. Then, different energy-based criteria are tested in order to take into account different types of triaxiality and mean stress effects corrections. The fatigue lifetime results predicted by both of them show a good agreement with experimental results. [ABSTRACT FROM AUTHOR]