Clyde L. Briant

Bio: Clyde L. Briant is an academic researcher from Brown University. The author has contributed to research in topics: Grain boundary & Intergranular corrosion. The author has an hindex of 35, co-authored 188 publications receiving 4483 citations. Previous affiliations of Clyde L. Briant include Max Planck Society & Colorado School of Mines.

Chromium depletion in the vicinity of carbides in sensitized austenitic stainless steels

Abstract: The analytical electron microscope (AEM) was used to examine the microstructure of type 316LN stainless steel alloys which had been annealed for 50 to 300 hours in the temperature range 600 to 700 °C. The M23C6 carbide chemistry and distribution are described as a function of heat treatment.X-ray spectroscopy in the AEM revealed significant chromium depletion at grain boundaries in the vicinity of carbides for samples aged at 50 and 100 hours at 650 °C and 100 and 300 hours at 700 °C, with lower grain boundary chromium values observed at 650 °C than at 700 °C. The width of the chromium depleted zone normal to the grain boundaries increased with increasing annealing time and/or temperature. Measurements of chromium concentration along the grain boundaries away from a carbide were made after aging at 700 °C for 100 hours, and the chromium level rose steadily until the bulk value was reached at a distance of ~3μm from the carbide. The width of the chromium depleted zone normal to the boundaries in the same sample was an order of magnitude less. Some molybdenum depletion was also found at the grain boundaries, and the Mo-depletion profiles were in form and extent similar to the chromium results. Simple thermodynamic models were used to calculate the equilibrium value of chromium at the carbide-matrix interface, and the chromium distribution along and normal to the grain boundaries. The results of these models agreed well with the AEM results, and the agreement can be improved by considering the effect of electron probe configuration on the AEM measurements. The calculated thermodynamic data and the AEM results were related to the corrosion behavior of the alloys. The occurrence of severe asymmetries in some concentration profiles normal to the grain boundaries, which increased with increasing annealing temperature or time, was shown to be due to boundary movement during the discontinuous precipitation of M23C6 carbides.

Hydrogen assisted cracking of type 304 stainless steel

Abstract: This paper reports a study of hydrogen assisted cracking in type 304 stainless steel. It shows that the most detrimental effect in increasing the susceptibility of the material to hydrogen cracking is the formation of martensite upon deformation. This is particularly damaging if the martensite is localized at the grain boundaries. With martensite present intergranular impurities such as phosphorus play a secondary role. As martensite becomes more difficult to form, the importance of impurities increases.

The preparation of “1223” Tl-Ca-Ba-Cu-oxide superconducting films via the reaction of silver-containing spray deposited Ca-Ba-Cu-Oxide with thallium oxide vapor

Abstract: A process is described for the preparation of superconducting films of “1223” TlxCa2Ba2Cu3Oy (0.65 10 000 A/cm2 was measured at 60 K-2 T with the magnetic field applied parallel to the crystallographic c-axis of the film.

Recent developments in stainless steels

Abstract: 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.

Thiol–enes: Chemistry of the past with promise for the future

Abstract: The photopolymerization of mixtures of multifunctional thiols and enes is an efficient method for the rapid production of films and thermoset plastics with unprecedented physical and mechanical properties. One of the major obstacles in traditional free-radical photopolymerization is essentially eliminated in thiol–ene polymerizations because the polymerization occurs in air almost as rapidly as in an inert atmosphere. Virtually any type of ene will participate in a free-radical polymerization process with a multifunctional thiol. Hence, it is possible to tailor materials with virtually any combination of properties required for a particular application. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5301–5338, 2004