Depending on the starting equilibrium temperature, the application of a magnetic field on a sample of Ni–Mn–Sn produces sample heating or cooling during adiabatic experiments. The competition between endothermal and exothermal effects is observed close to the martensite-to-austenite magnetostructural phase transition. A model assuming the coexistence of two phases and a field dependence of thei...

The texture of cold-rolled and heat-treated TiNi sheet has been measured and designated as {110}(1i0)p. This material has been used in thermal fatigue tests during and after which the anisotropy and development of several thermomechanical properties, such as transformation temperatures and strains, have been measured. Furthermore, the resulting changes of texture after thermal fatigue are prese...

Shape Memory Alloys (SMAs) undergo stress and temperature induced reversible diffusionless crystalline phase transformations between a high synmaetry phase (austenite) stable at high tenlperatures and low stresses, and a low symmetry phase (martensite) stable at low temperatures and high stresses. Unusual macroscopic effects arise from these crystallographic changes, chiefly shape memory and su...

An Fe-16MndSi alloy exhibits a good one-way and a little two-way shape memories by the stress induced y + E martensitic transformation and its reversion on heating and cyclic thermal y 2 E transformations, respectively. An intrusion of small amount of a' martensite at the initial shape change is not found to deteriorate the one-way memory and rather enhance the two-way memory. The two Fe-Mn-C a...

Martensitic steels form a material class with a versatile range of properties that can be selected by varying the processing chain. In order to study and design the desired processing with the minimal experimental effort, modeling tools are required. In this work, a full processing cycle from quenching over tempering to mechanical testing is simulated with a single modeling framework that combi...

Dual phase steels with different martensite volume fraction and morphology were tensile tested at a temperature range of 25 to 5500C. Stress-strain curves of all steels showed serration flow at temperatures of 250 and 3500C, and smooth flow at the other temperatures. Both yield and ultimate tensile strengths increased with increasing testing temperature up to about 450<sup...

Microstructural analyses of thermal or mechanical fatigued Nitinol show remarkable similarities and are characterized by an increase in dislocation density with increasing number of cycles. Dislocation bands, which are thought to be due to the effects of moving martensite interfaces, align with the martensite lattice invariant plane. These microstructural effects result in modification of trans...

Transformation induced plasticity (TRIP) assisted steels contain a small quantity of carbon enriched retained austenite, which transforms into martensite during the course of plastic deformation. Transformation of this kind can be induced by both stress and plastic strain. The detailed mechanism by which the martensite is induced is different for these two scenarios. An attempt is made here to ...

A Fe-34.5 wt % Mn-0.04 wt % C ultra-high Mn steel with a fully recrystallised fine-grained structure was produced by cold rolling and subsequent annealing. The steel exhibited excellent cryogenic temperature properties with enhanced work hardening rate, high tensile strength, and high uniform elongation. In order to capture the unique mechanical behaviour, a constitutive model within finite str...