Related papers: Modulated Martensite: Why it forms and why it defo…
The evolution of multivariant patterns in thin plates of magnetic shape memory materials with an applied magnetic field was studied theoretically. A geometrical domain-model is considered composed of straight stripe-like martensite variants…
We study through the time evolution of magnetization the low temperature (T) dynamics of the metastable coexisting phases created by traversing different paths in magnetic field (H) and T space in a shape memory alloy system,…
For multi-stage, displacive structural transitions we present a general framework that accounts for various intermediate modulated phases, elastic constant, phonon and related thermodynamic anomalies. Based on the presence or absence of…
Ferromagnetic shape memory alloys Ni$_{2+x}$Mn$_{1-x}$Ga were studied in the range of compositions $0.16 \le x \le 0.36$. Experimental phase diagram, constructed from differential scanning calorimetry, transport and magnetic measurements,…
Martensitic materials show a complex, hierarchical microstructure containing structural domains separated by various types of twin boundaries. Several concepts exist to describe this microstructure on each length scale, however, there is no…
A thermodynamically consistent multiphase phase-field approach for stress and temperature-induced martensitic phase transformation at the nanoscale and under large strains is developed. A total of N independent order parameters are…
Using a variational model based on non-linear elasticity we investigate whether in a cubic-to-tetragonal phase transformation it is energetically preferable to nucleate martensite within austenite. Under minimal growth assumptions on the…
Tailoring the phase stability and magnetic structure by combining the antiferromagnetic MnNiGe martensite with ferromagnetic MnFeGe austenite, a magnetic-field-induced martensitic transformation has been achieved in MnNi1-xFexGe system. The…
The carbon atom distribution in a tempered martensitic steel processed by cold drawing was investigated with a three-dimensional atom probe. Data clearly show that cementite starts to decompose at the early stage of deformation. This…
The irreversibility of the martensite transition in magnetic shape memory alloys (MSMAs) with respect to external magnetic field is one of the biggest challenges that limits their application as giant caloric materials. This transition is a…
We have studied the phase volume fraction related magnetoresistance (MR) across the first order martensite transformation (MT) of Ni44Cu2Mn43In11 alloy. Within the metastability of MT, an isothermal application of magnetic field converts…
Understanding the mechanism of martensitic transformation is of great importance in developing advanced high strength steels, especially TRansformation-Induced Plasticity (TRIP) steels. The TRIP effect leads to enhanced work-hardening rate,…
The mechanism of appearance of exponentially large number of metastable states in magnetic phases of disordered Ising magnets with short-range random exchange is suggested. It is based on the assumption that transitions into inhomogeneous…
Materials which can undergo slow diffusive transformations as well as fast displacive transformations are studied using the phase-field method. The model captures the essential features of the time-temperature-transformation (TTT) diagrams,…
A new $\beta$-metastable Ti-alloy is designed with the aim to obtain a TWIP alloy but positioned at the limit between the TRIP/TWIP and the TWIP dominated regime. The designed alloy exhibits a large ductility combined with an elevated and…
In situ neutron diffraction of the uniaxial tension test was used to study the effect of the surrounding matrix microstructure on the mechanical stability of retained austenite in high-carbon bearing steels. Comparing the samples with…
We study microstructure formation in two nonconvex singularly-perturbed variational problems from materials science, one modeling austenite-martensite interfaces in shape-memory alloys, the other one slip structures in the plastic…
The Prototypical magnetic memory shape alloy Ni$_2$MnGa undergoes various phase transitions as a function of temperature, pressure, and doping. In the low-temperature phases below 260 K, an incommensurate structural modulation occurs along…
Acoustic emission signals are known to exhibit a high degree of reproducibility in time and show correlations with the growth and shrinkage of martensite domains when athermal martensites are subjected to repeated thermal cycling in a…
Functional behavior of NiTi shape memory alloys is restricted to temperatures below 150 {\deg}C. To shed light on the origin of the loss of functional properties of NiTi with increasing temperature, we have investigated stress induced…