ALEMI: A Ten-Year History of Discussions of Alloying-Element Interactions with Migrating Interfaces

Abstract

ALEMI is concerned with the interactions between Alloying Elements and Migrating Interfaces. A first meeting was held in conjunction with the 2000 TMS Fall Meeting in St. Louis, MO. About 22 attendees endorsed the principles contained in the invitation, which envisaged a more collaborative approach to the study of alloying element interactions with transformation interfaces, especially in alloy steels. The meetings were intended to be informal workshops emphasizing the sharing of ideas and plans for research. The development of a shared stock of alloys for research was planned, as well as the publication of summaries of discussions in an open, preferably archival, forum. Eight further meetings were held, often in conjunction with major conferences. An approximate equilibrium developed between discussions of theoretical matters and experimental results and methods. A remarkable number of those who attended the first meeting in St. Louis continued to participate. Research ideas were put forward, issues debated, collaborations fostered, and the science of transformation interfaces advanced.

Reflections on the Analysis of Interfaces and Grain Boundaries by Atom Probe Tomography

“…In steels, the allotropic transformation from the high-temperature face-centered cubic (fcc) phase to the low-temperature body-centered cubic (bcc) is one of the degrees of freedom that can be used to adjust the alloy's properties. The partitioning of solutes between the bcc-ferrite and fcc-austenite and their interactions with migrating α–γ interfaces during the growth of ferrite has been a topic of intense research for decades, as recently reviewed thoroughly (Purdy et al, 2011; Gouné et al, 2015). Modeling the growth of ferrite in low alloyed steels has been extensively investigated because of its great importance for the design of new steel grades (Guo & Enomoto, 2007).…”

In Situ High-Temperature EBSD and 3D Phase Field Studies of the Austenite–Ferrite Transformation in a Medium Mn Steel

“…In steels, the phase transformation from austenite ( γ ) to ferrite ( α ) and vice versa proceeds by migration of their interfaces (Purdy et al, 2011) and this migration behavior can be used to control the final mechanical properties (Ashby, 2013). Excluding local topology effects, the interface migration behavior depends on the dissimilarities in crystal structure between both phases and the average chemical composition of the alloy, but even more so the local chemical compositions at the interface and the transformation temperature (Purdy, 1978 a , 1978 b ).…”

Solutions for Critical Raw Materials under Extreme Conditions: A Review

“…The development of modern steels, superalloys and other technologically important materials depends on a profound understanding of the function of alloying elements and in particular their role in the phase transformations. Examples for recent advances mainly in the field of steels are, e.g., reported in two review papers [ 111 , 112 ] from the ALEMI (Alloying Elements on Migrating Interfaces) group. By means of modern characterization techniques (in situ tension and bending experiments, high resolution backscatter diffraction mapping, transmission electron microscopy and synchrotron X-ray diffraction analysis) and thermodynamic modeling, it is demonstrated in [ 113 ] that due to a grain size-dependent competition between mechanical twinning and deformation-induced phase transformation, unexpectedly smaller austenite grains are less stable.…”