Influence of heat treatment on the texture, microstructure and tensile deformation behaviours of cold rolled FeCoNiCr sheets

The textures, microstructures and plastic deformation behaviours of equiatomic FeCoNiCr alloys treated by various annealing temperatures are investigated in this paper. Texture and microstructure analysis was performed by electron backscatter diffraction and transmission electron microscopy. The mechanical properties were evaluated using uniaxial tensile testing. The remarkable recrystallization presents at the temperature between 600 °C-800 °C. As the heat treatment temperature achieving to 800 °C, the content of high-angle boundaries, recrystallization fraction and the average grain size value will rise to ∼91%, ∼87.2% and ∼2.8 μm, respectively. With annealing temperature increase, the main textures including S, Brass and Goss/Brass weaken gradually. However, the content of random texture will elevate to ∼65% when temperature reach to 800 °C, which is related to generation process of annealing twin boundaries. For the sample with different recrystallization degree, its flow stress and strength-ductility balance level can be evaluated by the models constructed by considering the inhibition role of twin/stacking fault and the linearity relationship between strength and recrystallization fraction, respectively.