Comparison of damage development depending on the local microstructure in low alloyed Al-TRIP-Steels, IF steel and a DP steel
J. Imlau, W. Bleck, S. Zaefferer.
International Journal of Materials Research, 100, 584-593, (2009)
A study of the microstructural effects on the void initiation and crack growth in aluminium alloyed TRIP (transformation induced plasticity) steels has been conducted. Understanding of this microstructural dependency of the crack development is necessary to increase the failure limit and the energy absorption rate of the material.
Different microstructures in terms of phase volume fractions and spatial arrangement of these phases have been obtained by annealing. Additionally, different austenite stabilities, both geometrically as well as chemically based. have been obtained. First the macroscopic mechanical properties are linked to the microstructures. Furthermore, different characteristic prestraining levels are subsequently con-elated to the microstructures damage evolution by observation of the samples with backscatter electron diffraction-based orientation microscopy in a high resolution scanning electron microscope.
The experiments result in a prediction of the most critical microstructures parameters when high damage tolerance is needed.
Keyword(s): TRIP-steel; damage; void nucleation; crack growth; mechanical properties