Martensitic transformation plays a pivotal role in the microstructural evolution and plasticity of many engineering materials. However, so far the underlying atomic processes that accomplish the displacive transformation have been obscured by the difficulty in directly observing key microstructural signatures on atomic scale. To resolve this long-standing problem, here we examine an AISI 304 au...

Diffusionless phase transitions are at the core of the multifunctionality of (magnetic) shape memory alloys, ferroelectrics and multiferroics. Giant strain effects under external fields are obtained in low symmetric modulated martensitic phases. We outline the origin of modulated phases, their connection with tetragonal martensite and consequences for their functional properties by analysing th...

The effects of a high-velocity impact on the microstructure, phase transformation and mechanical property of aged Ti49Ni51 alloy are investigated. The transformation behavior and microstructure along the impact direction after impact emerge with regionalization characteristics, including a deformed region near the crater (0-4 mm) and an un-deformed region of the distal crater (5-6 mm). Stress-i...

Herein, considerable insight is provided into the evolution of strain-induced martensite and mechanical properties Fe–19Cr–4Ni–3Mn–0.15N–0.15C wt% austenitic stainless steel (in short Cr19NC15.15) during deformation at room temperature cryogenic temperatures. In situ magnetic measurements tensile tests various temperatures are conducted. The triggering stress ? trigg. ? ? ? ? required for forma...

The deformation mechanism of lean duplex stainless steel (LDSS) is overly complex not only by their dual phase microstructure, but also due to metastable austenite, which can deform different mechanisms and transform martensite strain. purpose this study was investigate the tensile test on low deformed cold-rolled samples (4%-22%) a 2304 LDSS. microstructure analyzed X-ray diffraction, optical ...

Thermodynamically consistent phase fi eld approach (PFA) for multivariant martensitic phase transformations (PTs) and twinning for large strains is developed [1, 2]. Thermodynamic potential in hyperspherical order parameters is introduced, which allowed us to describe each martensite-martensite (i.e., twin) interface with a single order parameter [3]. These theories are utilized for fi nite ele...

Abstract Martensite is a needle-shaped microstructure formed by rapid, diffusionless transformation and significantly affects the mechanical properties of materials. Here, in two-dimensional ReS 2 we show that martensite-like domain structures can form via transformation, involving small lattice deformations. By analyzing strain distribution topology as-grown chemical vapor deposition samples, ...

The features of martensite transformation in Fe (31 32)% Ni melt-quenched alloys are considered. The meltquenching was realized by spinning technique with variable parameters. The influence of the melt-quenching on structural and kinetics transformation parameters is revealed. In particular Ms point is shown to decrease but volume percentage of athermal martensite is found to be invariable with...

The unique concept of phase reversion involving severe deformation parent austenite into martensite, followed by annealing for a short duration, whereby the strain-induced martensite reverts to austenite, was adopted obtain nano-grained/ultrafine-grained (NG/UFG) structure in Cu-bearing biomedical austenitic stainless steel resulting high strength-high ductility combination. Work hardening and ...