It becomes possible in appropriate circumstances for similarly oriented plates of bainite or martensite to merge and form coarse crystallographically homogeneous domains whose presence leads to a deterioration in mechanical properties. A method is presented here for breaking up such domains, by introducing very small scale chemical composition variations in the austenite prior to its transforma...

The mechanical behaviour associated to the martensitic transformation has been modelled using a 2D FE description. The martensite variants are constituted of different elements of the mesh and four different variants are allowed to transform in the grain. The transformation progress is prescribed using a thermodynamical criterion based on the maximal work associated to the variant formation. Tr...

The microstructure and mechanical properties of Zr48Cu48 - x Al4M x (M ≡ Fe or Co, x = 0, 0.5, 1 at.%) metallic glass (MG) composites are highly dependent on the amount of Fe or Co added as microalloying elements in the parent Zr48Cu48Al4 material. Addition of Fe and Co promotes the transformation from austenite to martensite during the course of nanoindentation or compression experiments, resu...

Displacive transformations involve the disciplined motion of atoms. As a result, there are clearly defined relationships between all aspects of the parent and product lattices. The theory for this is well established but has not been exploited in the calculation of transformation textures. This paper is a critical assessment of the methods for the estimation of crystallographic textures during ...

The quantitative characterization of the microstructure evolution in high-Mn steel during deformation is of great importance to understanding its strain-hardening behavior. In the current study, in situ high-energy synchrotron X-ray diffraction was employed to characterize the microstructure evolution in a Fe-17Mn-1.5Al-0.3C steel during a tensile test. The microstructure at different engineeri...

In view of the fact that three kinds of phase transformations, i.e. aneutectoid decomposition β→ α+γ2, an ordering transformation β→ β1, and a martensitic transformation β1→ β' have been observed on isothemlal holding and cooling at different rates from the β region in Cu-Al binary alloys, the author has tried to obtain the T/T/T diagrams in order to show the correlations between these three tr...

The microstructure and martensitic transformation in the Ni-36.3Al-0.1Y (in at.%) alloy were investigated after ho~nogenisation and plastic deformation by hot upsetting at 1100°C. The alloy exhibited large, recrystallised grains of the Ni-A1 P phase wit11 spl~erical precipitates inside the grains and a thin layer of other phases located at the grain boundaries. The SEM and EDX analysis showed t...

Following the mathematical approach of Kelly (2003), rigorous version of infinitesimal deformation approach (ID) was applied to analyze fcc  bcc martensitic phase transformation observed in Fe-31wt Ni alloys considering the twinning shear system as the lattice invariant system (LIS). The expressions for crystallographical parameters associated with the martensitic phase transformation such as...