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

Stainless steel in construction: A review of research, applications, challenges and opportunities

http://doras.dcu.ie/17607/1/Review_of_residual_stresses-Final.pdf

Methods of measuring residual stresses in components

Creating lightweight, mechanically robust materials has long
been an engineering pursuit. Many siliceous skeleton species—
such as diatoms, sea sponges and radiolarians—have remarkably
high strengths when compared with man-made materials
of the same composition, yet are able to remain lightweight
and porous1–7. It has been suggested that these properties
arise from the hierarchical arrangement of different structural
elements at their relevant length scales8,9. Here, we report the
fabrication of hollow ceramic scaffolds that mimic the length
scales and hierarchy of biological materials. The constituent
solids attain tensile strengths of 1.75 GPa without failure
even after multiple deformation cycles, as revealed by in situ
nanomechanical experiments and finite-element analysis. We
discuss the high strength and lack of failure in terms of stress
concentrators at surface imperfections and of local stresses
within the microstructural landscape. Our findings suggest that
the hierarchical design principles offered by hard biological organisms
can be applied to create damage-tolerant lightweight
engineering materials.

/pdf/fabrication-and-deformation-of-three-dimensional-hollow-1s9akh4i88.pdf

Fabrication and deformation of three-dimensional hollow ceramic nanostructures

Experiments on stainless steel hollow sections—Part 1: Material and cross-sectional behaviour

http://spiral.imperial.ac.uk/bitstream/10044/1/66422/2/Metal%203D%20printing%20in%20construction%20-%20LG.pdf

Metal 3D printing in construction: A review of methods, research, applications, opportunities and challenges

This article describes numerical modeling of the structural response of stainless steel hollow sections. The aim of the investigation was to develop a consistent approach to the modeling of stainless steel structures. The developed finite element models are more sophisticated than any other reported attempts to model stainless steel structural behavior, with general expressions defined for material stress-strain behavior, enhanced strength corner properties, initial geometric imperfection modes, and amplitudes (local and global), and residual stresses. The general expressions define a consistent means of describing the key input parameters. A compound (two-stage) Ramberg-Osgood model is developed to describe stainless steel material stress-strain behavior in tension and compression. For the prediction of enhanced strength corner properties, a simple, though accurate model is proposed. Characterization of local plate imperfection amplitudes is described whereby a model originally devised for hot-rolled carbon steel cross sections was recalibrated and applied to stainless steel cross sections. Numerical prediction of the key performance measures from tests is achieved with a high degree of accuracy: On average, ultimate load was predicted to within 3 percent and with a low standard deviation; deformation at ultimate load was within 6 percent, but exhibited a higher standard deviation; and the general form of the load-deformation response and the failure modes were similar.

Numerical Modeling of Stainless Steel Structural Components—A Consistent Approach

http://spiral.imperial.ac.uk/bitstream/10044/1/42668/2/Arrayago%20et%20al%20%282015%29%20-%20Description%20of%20stress-strain%20curves%20for%20stainless%20steel%20alloys.pdf

Description of stress-strain curves for stainless steel alloys

The past 15 years have seen the introduction or major revision of structural stainless steel design codes throughout the world, and at the same time, interest in the use of stainless steel in construction has been accelerating. Historically the high initial material cost of stainless steel has limited its use primarily to specialist and prestige applications. However, the emergence of design codes, a better awareness of the additional benefits of stainless steel and a transition towards sustainability are bringing more widespread use into conventional structures. Although a number of similarities between stainless steel and ordinary carbon steel exist, there is sufficient diversity in their physical properties to require separate treatment in structural design. In addition to the straightforward differences in basic material properties (such as Young's modulus and yield strength), further fundamental differences exist, such as the nature of the stress–strain curve and the material's response to cold-work and elevated temperatures; these have implications at ultimate, serviceability and fire limit states. This paper describes the use of stainless steel as a structural material, discusses current structural design provisions, reviews recent research activities and highlights the important findings and developments.

Leroy Gardner

Papers

Experiments on stainless steel hollow sections—Part 1: Material and cross-sectional behaviour

Metal 3D printing in construction: A review of methods, research, applications, opportunities and challenges

Numerical Modeling of Stainless Steel Structural Components—A Consistent Approach

Description of stress-strain curves for stainless steel alloys

The use of stainless steel in structures