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

Abstract The historical background, research development, and the state-of-the-art of finite time thermodynamic theory and applications are reviewed from the point of view of both physics and engineering. The emphasis is on the performance optimization of thermodynamic processes and devices with finite-time and/or finite-size constraints, including heat engines, refrigerators, heat pumps, chemical reactions and some other processes, with respect to the following aspects: the study of Newton's law systems, an analysis of the effect of heat resistance and other irreversible loss models on the performance, an analysis of the effect of heat reservoir models on the performance, as well as the application for real thermodynamic processes and devices. It is pointed out that the generalized thermodynamic optimization theory is the development direction of finite thermodynamics in the future.

Finite Time Thermodynamic Optimization or Entropy Generation Minimization of Energy Systems

Review on titanium and titanium based alloys as biomaterials for orthopaedic applications.

Silver, known in metallic form since antiquity, has very early been recognized by mankind for its antimicrobial properties, a phenomenon observed, for example, in the context of drinking water (a silver coin in a well), food (silver cutlery, water storage recipients), and medicine (silver skull plates, teeth). Silver compounds were also shown to be useful. For example, dilute solutions of silver nitrate served long, and still do in some countries, as antimicrobial ointment to be instilled into Published in \" \" which should be cited to refer to this work.

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Nanobio Silver: Its Interactions with Peptides and Bacteria, and Its Uses in Medicine

A review of modified DLC coatings for biological applications

Influence of surface melting on dry rolling-sliding wear of aluminium bronze against steel

Low temperature plasma surface alloying with nitrogen (nitriding) and carbon (carburising) has been conducted to enhance the wear and corrosion resistance of AISI 316 austenitic stainless steel. In addition to detailed general characterisation of the microstructure and carbon and nitrogen depth profiles, a series of wear corrosion tests were carried out, employing a recently developed electrochemical scratching technique, to study the simultaneous effects of corrosion and wear. Results show that both plasma nitriding and carburising can improve the corrosion wear resistance of AISI 316 austenitic stainless steel but that the nitrided layer out performs the carburised layer.

Runner-up Corrosion Wear Behaviour of Low Temperature Plasma Alloyed 316 Austenitic Stainless Steel

Austenitic plasma nitrocarburising treatments of a medium carbon steel (0.47 wt.% C) have been carried out using a modified DC plasma furnace in a gas mixture of nitrogen, hydrogen and organic vapour of C 6 H 6 . Various gas compositions and treatment procedures have been used in order to produce a thicker monophase e carbonitride compound layer on the carbon steel surface. The nitrocarburised layers have been examined with several analytical techniques including X-ray diffraction, glow discharge spectrometry, metallographic and microhardness tests. It has been found that austenitic plasma nitrocarburising with organic vapour as the carbon source can readily produce a desirable monophase e compound layer on the investigated plain carbon steel surface. The e compound layer is supported by an austenite layer followed by a diffusion layer which is expected to give higher load bearing capacity. It has also been found that the “two-step” plasma nitrocarburising process is advantageous over the “one-step” process since the monophase e compound layer produced by the two-step process can be thicker, and the treatment temperature or the total treatment time can be reduced.

Austenitic plasma nitrocarburising of carbon steel in N2–H2 atmosphere with organic vapour additions

SUMMARY There can be little doubt that the emerging surface technologies which enable surface properties to be tailored to meet specific design criteria will expand significantly in coming years. A new journal, Surface Engineering, was launched by the Institute of Metals (London) in January 1985 in response to a demand from designers and materials engineers for a single comprehensive source of up-to-date information covering all aspects of surface engineering. The present paper has been abstracted largely from Surface Engineering.

T. Bell

Papers

Influence of surface melting on dry rolling-sliding wear of aluminium bronze against steel

Runner-up Corrosion Wear Behaviour of Low Temperature Plasma Alloyed 316 Austenitic Stainless Steel

Austenitic plasma nitrocarburising of carbon steel in N2–H2 atmosphere with organic vapour additions

Surface Engineering: A Rapidly Developing Discipline.

Hardening response and tempering behaviour of electron beam surface melted Ti–8.5Si alloy