In situ multiaxial loading during neutron diffraction tests were undertaken on a low-alloyed Quenched and Partitioning (Q&P) Transformation Induced Plasticity (TRIP) Bainitic Ferrite (TBF) steel with dispersed austenite particles. The effect of stress triaxiality the evolution deformation-induced martensite is investigated under uniaxial- equibiaxial-tension as well tension/compression ratio −1...

The purpose of this review was to investigate the correlation between magnetism and crystallographic structures as it relates to the martensite transformation of Ni2MnGa type alloys, which undergo martensite transformation below the Curie temperature. In particular, this paper focused on the physical properties in magnetic fields. Recent researches show that the martensite starting temperature ...

An experimental arrangement is demonstrated that overcomes some difficulties in thermo–mechanical testing of thin Shape Memory Alloy (SMA) wires under uniaxial tension. It is now well known that stress–induced transformations in some SMAs under uniaxial loading can lead to mechanical instabilities and propagating phase transformation fronts. Critical parameters, such as nucleation barriers are ...

Abstract Cryogenic turning can be used to produce deformation-induced martensite in metastable austenitic steels. Martensite exhibits a higher hardness than austenite and increases the wear resistance of workpiece. In order reliably induce desired content subsurface zone during process, non-destructive, contactless real-time testing method is necessary. Eddy current an electromagnetic that non-...

Kinetic dependence of martensitic transformation and properties changes in Fe-24%Ni5%Mo alloys with different carbon content have been obtained. Internal friction method was used for the precise investigation of structural changes after austenization, during martensitic transformation at sub zero temperature and during the postheat. The influence: (i) of frequency of oscillations, (ii) rate of ...

Hot–press forming steels are formed in a fully austenitic state followed by die– quenching in order to generate martensite and achieve a strong steel. The ductility however, tends to be limited. We explore in this work a novel steel design in which the forming operation is in the two–phase austenite and ferrite field, so that the quenching results in a dual–phase ferrite and martensite microstr...

A 3D finite-strain constitutive model for the deformation response of NiTi at single crystal level is proposed. The accounts reversible phase transformation from austenite to martensite habit plane variants, plastic in phase, and rate effects induced latent heat. It developed within formalism irreversible thermodynamics with internal state variables based on Eulerian logarithmic strain its corr...

The Ginzburg-Landau theory for multivariant martensitic phase transformations is advanced in three directions: the potential is developed that introduces the surface tension at interfaces; a mixed term in gradient energy is introduced to control the martensite-martensite interface energy independent of that for austenite-martensite; and a noncontradictory expression for variable surface energy ...

A Fe-0.15C-5Mn-0.5Si-0.05Nb medium Mn steel annealed at 660℃ and 685℃ both exhibited inhomogeneous deformation with Lüders extremely high work hardening rates, but different strain behavior. In-situ neutron diffraction measurements during tensile test were performed to investigate changes in the phase stresses contributed strength of constituent phases, crystal orientation austenite. The role e...

In order to discuss the advent of the magnetic-field-induced strains for a single crystal Fe22:0Ni51:5Ga26:5 shape memory alloy, the magnetic easy axis in the 14M martensite phase and the magnetocrystalline anisotropy constant K have been investigated. From the data on the spontaneous thermal expansion and the magnetization curves, the magnetic easy axis of the 14M martensite phase was determin...