This -paper corrects an error in a previous paper by Dechamps and Brown and presents a much improved model for the structure of -twins in Fe-Ni martensite. The model is based upon the dissociation of screw dislocations under the stress due to the martensitic transformation. Resume-Dans cet article, nouscorrigeons une erreurd'un article preced~nt de Dechamps et Brown et nous presentons un modele...

An open question is the underlying mechanisms for a recent discovered nanocomposite, which composed of shape memory alloy (SMA) matrix with embedded metallic nanowires (NWs), demonstrating novel mechanical properties, such as large quasi-linear elastic strain, low Young's modulus and high yield strength. We use finite element simulations to investigate the interplay between the superelasticity ...

The different contributions to the entropy change linked to the austenite-martensitic transition in a Ni-Mn-Sn metamagnetic shape memory alloy have been determined by combining different experimental techniques. The vibrational contribution has been inferred from the vibrational density of states of both the martensitic and austenite phases. This has been accomplished by combining time-of-fligh...

Phase field approach (PFA) to the interaction between phase transformations (PTs) and dislocations is developed at large strains as a nontrivial combination of our recent advanced PFAs to martensitic PTs and dislocation evolution. Finite element method (FEM) simulations are performed to solve the coupled phase-field and elasticity equations and are applied to study of the growth and arrest of m...

The paper considers the influence of aging of high-temperature phase on subsequent martensitic transformation in Cu-Al-Mn alloy. The morphology of behavior of martensitic transformation as a result of alloy aging under annealing in a constant magnetic field with different sample orientation relatively to the field direction and without field was studied for direct control of the processes of ma...

Elatresh et al. (1) (ECAHDB) claim that the lowtemperature martensitic structure of lithium “is not the heretofore assigned 9R.” This is based on comparing results of Fermi surface calculations to de Haas–van Alphen (dHvA) data from Springford and coworkers (2, 3). We note that Springford’s group took extensive steps to preserve the body-centered-cubic (bcc) structure and to avoid the temperatu...

The displacive transformation classification proposed at ICOMAT 79 [I] is reviewed in light of recent progress in mechanistic understanding. Issues considered include distinctions between shuffle transformation vs. self-accommodating shear, dilatation vs. shear-dominant transformation, and nucleated vs. continuous transformation. 1. HISTORICAL INTRODUCTION Cohen, Olson and Clapp (COC) at ICOMAT...

Microstructures of both as-quenched and intercritical-annealed medium-Mn steel were investigated by transmission electron microscopy to acquire a better understanding ?–? ?–?? martensitic transformations. The orientation relationships among each phases determined as (1¯10)??//(0001)?,[111]??//[112¯0]? for the case sample, (1¯10)??//(1¯11)?//(0001)?,[111]??//[110]?//[112¯0]? respectively. In add...

in this investigation, continuous cooling transformations and microstructures have been studied in detail in a low carbon ti-nb bearing microalloyed steel by means of dilatometry, metallography and hardness measurements. the results indicate that when the cooling rate is greater than 1˚c/s, the dilatation curve is associated with a major dilatation at relatively low transformation temperatures,...

Many crystalline materials exhibit solid-to-solid martensitic phase transformations in response to certain changes in temperature or applied load. These martensitic transformations result from a change in the stability of the material’s crystal structure. It is, therefore, desirable to have a detailed understanding of the possible modes through which a crystal structure may become unstable. The...