Tensile tests performed on materials of equal chemical compositionmay show entirely controversial elastic plastic characteristicsdepending on the preceding heat treatment. In the particular case oflow alloyed TRIP (transformation induced plasticity) steelsmanufacturers have managed to stabilize retained austenite at roomtemperature whose presence is commonly held responsible for asignificantly wide range of plastic straining before ultimatefailure. Such a material behavior is naturally desirable for deepdrawing processes. The applied tensile load gives rise to mechanicaldriving forces eventually triggering the transformation ofmicroregions of retained austenite into martensite. This phasechange, in turn, entails misfit strains large enough to initiateplastic yield around these newly formed martensitic inclusions. Thecurrent work focuses on the numerical quantification of the amount ofplastification. Finite element models of unit cells containing anumber of quasi-randomly oriented austenitic inclusions are used toinvestigate the influence of the volume fraction of retainedaustenite in the virgin material on the total elongation at fractureof the specimen. A comparison between the tendencies obtained in thenumerical analyses with experimental data reveal the importance oftaking into account metallurgical issues in order to satisfactorilyexplain the TRW phenomenon.
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