วันจันทร์ที่ 20 พฤษภาคม พ.ศ. 2556

CALPHAD (Calculation of Phase Diagrams) - A Comprehensive Guide

AppId is over the quota
AppId is over the quota

This excellent book is probably the first comprehensive guide to the CALPHAD method. CALPHAD is an acronym that was coined in the early 1970s and stands for CALculation of PHAse Diagrams.

The CALPHAD method is based on the fact that a phase diagram is a representation of the thermodynamic properties of a system. Thus, if the thermodynamic properties are known, it is possible to calculate the multi-component phase diagrams. In other words, thermodynamic descriptions of lower-order systems (e.g., the Gibbs energy of each phase) can be combined to extrapolate higher-order systems.

In metallurgical engineering, for example, the CALPHAD method is invaluable when it comes to understanding the relationship between the chemical composition of an alloy (typically based on complex higher-order systems), the processing conditions, the resulting microstructure, and the alloy's final properties. In addition, most alloys undergo one or more phase transformations during use. Such phase transformations can often be understood through the use of phase diagrams (and which now can be calculated, thanks to the CALPHAD method).

The book covers the history of the CALPHAD method; the laws and basic concepts of thermodynamics (enthalpy, heat capacity, chemical equilibrium, Gibbs energy, etc); various experimental techniques to measure thermodynamic quantities and to construct phase diagrams; thermodynamic models for solutions and compound phases (stoichiometric compounds, random substitutional models, sublattice models, ionic liquid models, and aqueous solutions); phase stabilities; short-range and long-range ordering models; the role of magnetic Gibbs energy; computational methods and thermodynamic optimization of phase diagrams; as well as the coupling of thermodynamics and kinetics.

Finally, a number of important practical examples where the CALPHAD method was successfully applied are given and described in detail. The examples include titanium-based Ti-6Al-4V alloy, aluminum casting alloys, corrosion-resistant duplex stainless steels, nickel-based superalloys, high-speed steels, sigma-phase formation, micro-alloyed steels, NiAl-based and TiAl-based intermetallic alloys, magnetic alloys, high-strength cobalt-nickel steels, slag and slag-metal equilibria, chemical vapor deposition processing, hot salt corrosion in gas turbines, and the effect of radiation on the precipitation of silicides in nickel-based alloys.

I highly recommend this book.



วันจันทร์ที่ 6 พฤษภาคม พ.ศ. 2556

Physics, Complexity, Gravity and the Universe - Humans at Home in Their Habitat

AppId is over the quota
AppId is over the quota

Physics is much about the nature of things in this realm we live. In this dimension there are laws and those laws as far as we can see seem to be consistent throughout our universe, perhaps everywhere for all we know. Thus, a bit of philosophy is in order to comprehend the order of things.

Perhaps, you have heard of Murphy's Law, well there is a good amount of reality behind complex systems, mathematically speaking, they more things you have running the more chances of one of them breaking. And maybe you have heard the thought that; simplicity breeds complexity, which in observation seems to be very true to our realm. To help illustrate these points and other topics which intersect this concept; I'd like to recommend this book;

"At Home in the Universe - the search for the laws of self-organization and complexity" by Stuart Kauffman. 1995

If you are looking for a book that takes all the observations, natural laws and known science and then poses the question and looks for the ultimate answers in complexity, chaos and natural self-organization from atoms and molecules to complex bio-systems and planetary systems. The author makes some great points in the book and takes the reader into deep thought.

The author considers snowflakes, oil on water, DNA, evolution, corporations, politics, government, and "the rise and fall of great civilizations." Kaufman also wrote the book; "the origin of order." This book also ponders the future of the human race and the future of Globalization, as the forward progression of mankind continues.

"Lance Winslow" - Online Blog Content Service. If you have innovative thoughts and unique perspectives, come think with Lance; www.WorldThinkTank.net/. Lance Winslow's Bio