Fig. 1: Maps of the deviatoric strain of the B2 austenite along the vertical y axis (εyy) from x-ray diffraction analysis. The global displacements for these maps are shown in the upper left corner of each image. The dark lines illustrate the approximate location of the edges of the diamond strut. The red color indicates tensile strain whereas blue indicates compressive strain; note also the pr...

Purpose: The aim of the paper is to design heat treatment conditions of dual-phase steel and to determine their influence on the structure and mechanical properties of steel. Design/methodology/approach: The heat treatment of the C-Mn steel in order to obtain a dual-phase ferritic – martensitic structure of desirable phase fractions was realized. To investigate the influence of heat treatment p...

The microstructure obtained as the weld cools from the liquid phase to ambient temperature is called the as–deposited or primary microstructure. Its major components include allotriomorphic ferrite, Widmanstätten ferrite, and acicular ferrite (Fig. 1). There may also be some martensite, retained austenite or degenerate pearlite. These latter phases occur in very small fractions, and are known b...

Due to recent concern about allergic and toxic effects of Ni ions released from TiNi alloy into human body, much attention has been focused on the development of new Ni-free, metastable beta-type biomedical titanium alloys with a reversible phase transformation between the beta phase and the alpha'' martensite. This study investigates the effect of the stress-induced alpha'' martensite on the m...

The stress-induced transformation behavior of retained austenite is considered in this work. With the development of transformationinduced plasticity (TRIP) steels this deformation mode is of growing importance. Twinned martensite structures were calculated using the crystallographic theory of martensite. An available work criterion was used to predict the transformation potentials for 16 diffe...

Nano/submicron austenitic stainless steels have attracted increasing attention over the past few years due to fine structural control for tailoring engineering properties. At the nano/submicron grain scales, grain boundary strengthening can be significant, while ductility remains attractive. To achieve a nano/ submicron grain size, metastable austenitic stainless steels are heavily cold-worked,...

the effect of ferrite grain size on the fatigue and tensile properties of dual phase steels with a 0.25 volumefraction of martensite (vm) under different heat treatments was investigated. the heat treatments werehomogenized at 1200 oc along with several subsequent normalizations at 910 oc, resulting in differentmicrostructures and mechanical properties. after heat treatment, the obtained steels...

In this research, variant selection of martensite transformed from ultrafine-grained (UFG) austenite fabricated by accumulative roll bonding (ARB) process and subsequent annealing was investigated with respect tomorphology of parentaustenitic phase. The results show that the original shape of austenite grain is very effective factor in determiningthe preferred variants of martensite transformed...

Examination of a time–temperature–transformation (TTT) diagram for an eutectoid carbon steel (Fig. 1), bearing in mind the fact that the pearlite reaction is essentially a high temperature one occurring between 550C and 720C and that the formation of the martensite is a low-temperature reaction, reveals that there is a wide range of temperature ∼250–550C within which neither of these phases for...

We study the symmetrised rank-one convex hull of monoclinic-I martensite (a twelve-variant material) in the context of geometrically-linear elasticity. We construct sets of T3s, which are (non-trivial) symmetrised rank-one convex hulls of three-tuples of pairwise incompatible strains. In addition, we construct a fivedimensional continuum of T3s and show that its intersection with the boundary o...