The strain–temperature response of Ni–Fe–Ga single crystals underscores the role of the inter-martensitic transformation in creating intersecting heating and cooling segments; the separation of these segments occurs due to irreversibilities at high stresses and at high temperatures. An ultra-narrow tensile (1 C) and compressive (<10 C) thermal hysteresis are observed for the A 10M 14M case, acc...

We report on the shape memory characteristics and magnetic behavior of polycrystalline and single crystalline FeNiCoTi. Predeforming the samples in the martensitic state and biasing of the martensite variants produced anisotropy in the magnetization behavior allowing the ‘easy axis’ to be identified as the ‘a-axis’ in the martensitic state. Based on these results, we provide an estimate of the ...

Many alloys display the shape-memory effect in single crystal form, however the degree to which they retain this effect in polycrystalline form varies widely. We propose a theoretical explanation for this difference, showing that the recoverable strain of a polycrystal depends on the texture of the polycrystal, the transformation strain of the underlying martensitic transformation and especiall...

Magnetic properties and martensitic transformation behaviors of NiCoMnAl metamagnetic shape memory alloys were investigated. The kinetic arrest phenomenon was observed at about 40K during thermomagnetization measurements. At temperatures ranging from 4.2 to 200K, magnetic field-induced reverse transformation was confirmed by a pulse magnetometer with a magnetic field up to 45 T. By plotting the...

In the present study, the effect of grain size on the austenite stability was studied by nanoindentation tests in a 304L stainless steel. Thermomechanical processing based on cold rolling and annealing was used to produce two different types of austenite: ultrafine grained (UFG) austenite with the average grain size of 0.65 μm and coarse grained (CG) austenite with the average grain size of 12 ...