Coarse crystals of martensite can form by the coalescence of thin individual platelets of martensite under appropriate circumstances. Although these coarse grains are essentially single crystals, there exist significant orientation gradients across their dimensions. It is demonstrated that these gradients arise because of the plasticity induced in austenite due to the transformation strain asso...

The influence of nitrogen (0 to 0.27 wtYo) on martensite formation in an experimental low-nickel stainless-steel alloy (Fe-17Cr-7Mn-4Ni) has been investigated. The alloys containing 0.1 wtYo or more nitrogen are fully austenitic at room temperature; those containing less nitrogen consist of a mixture of austenite, martensite and S-ferrite. The alloys containing less than 0.2 wtYo nitrogen are m...

Welded mild steel is used in different applications engineering. To strengthen the joint, weld can be reinforced by adding titanium alloy powder to joint. This results formation of incomplete martensite a welded The affects mechanical properties. Therefore, this study aims predict volume fraction butt joints understand complex phenomena during microstructure formation. do so, combination finite...

In this paper, the effects of carbon, Si, Cr and Mn partitioning on ferrite hardening were studied in detail using a medium Si low alloy grade 35CHGSA steel under ferrite-martensite/ferrite-pearlite dual-phase (DP) condition. The experimental results illustrated that an abnormal trend had occurred with progress formation. At first, microhardness decreased increasing volume fraction ferrite, the...

The redistribution of carbon after tempering of a novel nanocrystalline bainitic steel consisting of a mixture of supersaturated ferrite and retained austenite has been analyzed by atom probe tomography. No direct evidence supporting the additional carbon enrichment of austenite beyond that initially achieved during the bainite heat treatment was obtained during subsequent tempering of this hig...

Modern TRIP assisted steels contain retained austenite with carbon concentrations in excess of 1 wt-%. Some of their mechanical properties, in particular the toughness and ductility, rely on the diffusionless transformation of this austenite into high-carbon martensite, induced by stress and strain. The properties can be excellent in spite of the fact that freshly formed high-carbon martensite ...

Superelastic NiTi and NiTi-TiC composites were subjected to static uniaxial compressive loading while neutron diffraction spectra were simultaneously acquired. A methodology was established to obtain quantitative strain, texture and phase volume fraction information during the forward and reverse stress-induced martensitic transformation. Despite the presence of 10 vol. % of stiff TiC particles...

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 ...