This article presents an overview of the developments in stainless steels made since the 1990s. Some of the new applications that involve the use of stainless steel are also introduced. A brief introduction to the various classes of stainless steels, their precipitate phases and the status quo of their production around the globe is given first. The advances in a variety of subject areas that have been made recently will then be presented. These recent advances include (1) new findings on the various precipitate phases (the new J phase, new orientation relationships, new phase diagram for the Fe–Cr system, etc.); (2) new suggestions for the prevention/mitigation of the different problems and new methods for their detection/measurement and (3) new techniques for surface/bulk property enhancement (such as laser shot peening, grain boundary engineering and grain refinement). Recent developments in topics like phase prediction, stacking fault energy, superplasticity, metadynamic recrystallisation and the calculation of mechanical properties are introduced, too. In the end of this article, several new applications that involve the use of stainless steels are presented. Some of these are the use of austenitic stainless steels for signature authentication (magnetic recording), the utilisation of the cryogenic magnetic transition of the sigma phase for hot spot detection (the Sigmaplugs), the new Pt-enhanced radiopaque stainless steel (PERSS) coronary stents and stainless steel stents that may be used for magnetic drug targeting. Besides recent developments in conventional stainless steels, those in the high-nitrogen, low-Ni (or Ni-free) varieties are also introduced. These recent developments include new methods for attaining very high nitrogen contents, new guidelines for alloy design, the merits/demerits associated with high nitrogen contents, etc.

Recent developments in stainless steels

The electronic density of states (DOS) and magnetic moments of rare-earth antimonides (NdVSb3) has been studied by the first principles full-potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT). For the exchange-correlation potential, the GGA+U method is used. The effective moments of NdVSb 3 B was found to be 4.50 . The exchange-splittings of V-3d state electrons and 4f-states of Nd atoms were analyzed to explain the magnetic nature of these systems. The V atom plays a significant role on the magnetic properties due to the hybridization between V-3d and Sb-5p state orbitals. The results obtained are compared and found to be in qualitative agreement with the available results.

/pdf/a-first-principles-study-2dnb5j946i.pdf

A First Principles Study

It is known that nanocrystallites can form in shear bands produced during severe bending or high-energy ball milling of thin ribbons of a metallic glass. We present direct experimental evidence that highly confined and controlled local contact at the ultrafine scale in the form of quasi-static nanoindentation of a bulk glassy metal alloy at room temperature can also cause nanocrystallization. Atomic force microscopy and transmission electron microscopy show that nanocrystallites nucleate in and around shear bands produced near indents and that they are the same as crystallites formed during annealing without deformation at 783 kelvin. Analogous to results from recent experiments with glassy polymers, our results are reasoned to be a consequence of flow dilatation inside the bands and of the attendant, radically enhanced, atomic diffusional mobility inside actively deforming shear bands.

http://science.sciencemag.org/content/sci/295/5555/654.full.pdf

Nanocrystallization During Nanoindentation of a Bulk Amorphous Metal Alloy at Room Temperature

Dual-phase (DP) steel is the flagship of advanced high-strength steels, which were the first among various candidate alloy systems to find application in weight-reduced automotive components. On the one hand, this is a metallurgical success story: Lean alloying and simple thermomechanical treatment enable use of less material to accomplish more performance while complying with demanding environmental and economic constraints. On the other hand, the enormous literature on DP steels demonstrates the immense complexity of microstructure physics in multiphase alloys: Roughly 50 years after the first reports on ferrite-martensite steels, there are still various open scientific questions. Fortunately, the last decades witnessed enormous advances in the development of enabling experimental and simulation techniques, significantly improving the understanding of DP steels. This review provides a detailed account of these improvements, focusing specifically on (a) microstructure evolution during processing, (b) exp...

An Overview of Dual-Phase Steels: Advances in Microstructure-Oriented Processing and Micromechanically Guided Design

Increasing the temperature of jet engines requires materials that are stable against degradation. Towards this goal, growth of TiAl alloys with high strength and ductility, as well as superior creep resistance, is reported at high temperatures.

Polysynthetic twinned TiAl single crystals for high-temperature applications

Inhomogeneity in plastic deformation of two-phase steels

Mechanical surface treatment methods such as shot peening may improve the fatigue strength of materials. In this study, the effect of shot peening on strain controlled constant amplitude fatigue lo ...

Birger Karlsson

Papers

Inhomogeneity in plastic deformation of two-phase steels

Stability of shot peening induced residual stresses and their influence on fatigue lifetime

Microstructural evaluation and interpretation of the mechanically and thermally affected zone under railway wheel flats

Plastic deformation of eutectoid steel with different cementite morphologies

Plastic deformation of ferrite—pearlite structures in steel