Aero-engine Turbofan - Video shows simple working principles of a modern High By-pass Ratio Turbofan Aero-engine & materials working temperatures

The short video lasts about 3mns.  An we described video for main parts and working of a modern aircraft aero-engine such as those which equip the Airbus A320 family. A background must for aero-engine metallurgists ad materials students and professionals.

The interested viewer may see the air-flow which produces the aircraft thrust. This is done by accelerating the air from the front to the back of the engine largely (80%) by the large fan-propeller at the front of the engine.

The different turbines and blades and their roles within the engine are described. (The low and high pressure compressors (13 stages) which stage by stage increase the pressure as the air flows thru' them.

The combustion chamber where aircraft fuel mixed with air is burned, the high and low pressure turbines in which the hot gas pressure is reduced as they drive the compressors and propeller-fan. There are 5 stages, one high pressure and 4 low pressure. Finally we have the exhaust system.

NB.
The concentric shafts which connect the combustion area turbines to the front propeller and turbines are shown.The temperatures  in the turbine stages just before the combustion chamber reach 450°c and within the combustion chamber whose energy drives the fans reaches 1700°C .

More cf the video above.

Reference 1.

Atom probe crystallography - Review article - Materials Today

Atom probe crystallography - Review article - Materials Today

27 September 2012
Baptiste Gault, Michael P. Moody, Julie M. Cairney and Simon P. Ringer

Gault et al. address new developments in the emerging area of atom probe crystallography.

This review addresses new developments in the emerging area of “atom probe crystallography”, a materials characterization tool with the unique capacity to reveal both composition and crystallographic structure at the atomic scale. This information is crucial for the manipulation of microstructure for the design of both structural and functional materials with optimized mechanical, electric, optoelectronic, magnetic, or superconducting properties that will find application in, for example, nanoelectronics or energy generation. The ability to extract crystallographic information from 3D atomistic reconstruction has exciting potential synergies with modern modeling techniques, blending experimental and computational methods to extend our insight.

Click here to read the Full Text

Materials Today (2012) 15(9), 378-386

This is just one of the many features the interested reader will find in Elsevier's free materials science topical subjects magazine

Enjoy

The Institute of Physics have opened their Journal of Physics_Condensed Matter_Highlights for 2011 are freely available to read-download for a limited period (31Dec2012)

The Highlights 2011  are a collection for Journal of Physics: Condensed Matter. They include outstanding papers, fast track communications, topical reviews and special issues published in the journal over the last year. These articles were selected by the Editorial Board on the basis of a range of criteria including referee endorsements, citations and download levels, and simple broad appeal. 

The articles will be free to read until 31 December 2012.

This wealth of 1st class publications are available in the following 10 sub categories:

Surface, interface and atomic-scale science

Liquids, soft matter and biological physics

Nanostructures and nanoelectronics

Solid structure and lattice dynamics

Electronic structure

Correlated electrons

Superconductors and metals

Semiconductors

Dielectrics and ferroelectrics

Magnetism and magnetic materials             Read the Editorial Presentation in Pdf

FIND the fast track papers at this LINK

and 

The 20 best Topical Reviews based on downloads, Here but require an IOP subscription, sorry.

Sustainable Materials_with both eyes open_Free to download and read or to buy as hard cover_

Indispensable addition to  today's Materials Professionals and Designers Library.

This excellent book may be read for free at the following link

   Download the whole book in one PDF file [25Mb] 

Reviews may be found both on the book's website above, on the MaterialsToday site where I found reference to this excellent addition to the professional metallurgist, materials scientist and all involved in materials. Further this stimulated my memory as a regular reader of books reviewed by our professional materials scientists, technologists and engineers, members of The Institute- IOM3. Indeed I found  "Sustainable Materials_with both eyes open" reviewed for the Institute by Ian J. Bowbrick, (FIMMM)  Head of Professional Formation at The Royal Academy of Engineering. 

Executive summary by Ian who noted this book 10/10 which is an unusually high score.

"The story concludes by looking at the role business policymakers and individuals have in creating a sustainable materials future. The approach in ‘taking the fight’ to business is deftly handled. Realistically the authors cite that cost savings are too weak a driver for action by business and call on policymakers to kick-start the actions required. To this end, they propose a robust and detailed five-point plan. The story finishes with a useful pro-forma checklist for professionals looking to make a difference. 

I found this book to be well researched with reasoned and compelling arguments. Allwood and Cullen are to be congratulated on delivering a methodology that can be regarded as a paradigm shift to a new way of teaching and understanding materials science in the post-fossil fuel era society is now entering. This is essential reading for both student and practitioner, particularly those in senior management positions. 10/10." 

NB. For a full list of book reviews by IOM3 professionals all fully available to the interested specialist, non-member or motivated general public here is the

IOM3-Materials World BOOK REVIEW LINK.

Hope you have and enjoyable and profitable read.

Key facts about the Steel industry from the World Steel Association

As Europe struggles in the face of high growth emerging economies - "Europe
and the United States show a weakness in both GDP and industrial production as GDP is forecast to grow less than 2.0% in both 2011 and 2012, as opposed to an expected 9.0% and 7.5% growth in 2012 for China and India, respectively. (Ref 1. World Economic Outlook: Slowing Growth, Rising Risks, IMF, September 2011." whose role in economic downturns have been severely criticised by Nobel Economist Joseph Stieglitz as one of a bad lot of players, The Major US Bankers, their  followers, The anti-regulation lobby (lubby) The Frankenstein Labs for Innovation & Creativity of Wall Street, dixit JS)

I feel that I owe an atonement for neglecting this indispensable association of  the worlds steelmakers is ever more a necessity.

cf. links below taken from their website - many important reports and statistics are freely available.

Before the reader rushes down to these links let me draw your attention to the green background. Whether intentional or I surmise not, I was already thinking along these such a line. Environmental demands which must be brought to bare on these brave tough masculine environments.  Indeed the world Steel Association has drawn up a report entitled " Sustainable-steel-at-the-core-of-a-green-economy"

Sustainable-steel-at-the-core-of-a-green-economy.pdf

in particular let me draw the readers attention to Page 36 of the report

WHAT GOVERNMENTS AND POLICYMAKERS CAN DO TO HELP

I trust this may be of some help in our troubled Europe, in which the conservatives have raised a "hue & cry" for improved competitivity - ie more flexibility->lower wages (on average) at the lower levels, less people etc. Out side the industry the cry has reached top management (automobile industry - probably already squeezing the steelmaker to death- However I have never heard those who flex their vocal muscles and their financial clout to the extent of taking a huge cut in salary of the order of the crises they are so keen to underline.

I trust not everyone will enjoy reading this! 

Key facts about the Steel industry

• Steel: A key driver of the world's economy
• Sustainable steel
• Steel in your life
• Safe, innovative and progressive steel
• Life cycle thinking

Steel Research and how metallurgy helps you live longer_Free critical review of hot stamping technology and its integration with coating systems from Wiley_ Automobile Applications

"How Metallurgy Helps You Live Longer" is the title of the introduction to Tim Adams editor of Wiley's Journal Steel research International in his Materials Views "blog" 

The critical review was written by by Prof. Bruno De Cooman and Dr. Dong Wei Fan of Pohang University of Science and Technology (FREE access). It provides a comprehensive review of steel hot stamping technology and its integration with coating systems is given, including Zn-Ni coatings, hybrid sol-gel coatings, recently developed Al–Zn alloy coatings and dual layer Zn–Al and Zn–Al–Mg coatings.  The authors include discussions of the weldability, paintability, and corrosion resistance of these systems, making this an important article for manufacturers and engineers alike.

This is a paper well woth reading and addint to our personal professional library

LINK to Tim's Blog and article How Metallurgy Helps You Live Longer 

Link to the original paper on Wiley Online Library

Nano-material molecular electric conductivity is predicted to offer up to four times bulk conductivity depending on the material-molecules

The following news release from Brookhaven National Lab entitled

"Electronics Play By a New Set of Rules at the Molecular Scale"

September 2, 2012, By Aviva Hope Rutkin"

Nano-material molecular electric conductivity is predicted to offer up to four times bulk conductivity depending on the material-molecules

Atomic scale visualization of the single molecule junctions formed with two equivalent pathways (left) and one pathway (right), including the bonding to the tips of two gold electrodes and a schematic of the external electrical circuit.

In a paper published in Nature Nanontechnology onSeptember 2, 2012, scientists from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Columbia University’s departments of Chemistry and of Applied Physics explore the laws that govern electronic conductance in molecular scale circuits.

“Everyone who has worked with basic electronic circuits knows that there are some simple rules of the road, like Ohm’s Law,” explains collaborator Mark Hybertsen, a physicist at Brookhaven’sCenter for Functional Nanomaterials (CFN). Hybertsen provided the theory to model the observed circuit behavior with the CFN’s computational tools. “For several years we have been asking fundamental questions to probe how those rules might be different if the electronic circuit is shrunk down to the scale of a single molecule.”

Conductance measures the degree to which a circuit conducts electricity. In a simple circuit, if you hook the resistors up in parallel, the electrons can flow through two different paths. In this case, the conductance of the full circuit will simply be the sum of the conductance of each resistor. 

However, in a molecular circuit, the rules that govern current flow now involve fundamental quantum mechanics. In most single-molecule circuits, the molecules do not behave like conventional resistors; instead, the electrons tunnel through the molecule. When the molecule offers two pathways in parallel, the wave-like movement of an electron can dramatically change the way conductance adds up. For several years, experts in nanotechnology have suspected—but not proven—that quantum interference effects make the conductance of a circuit with two paths up to four times higher than the conductance of a circuit with a single path.

In order to investigate these quantum mechanical effects further, the scientists needed to construct their own controllable nano-size circuits. Working with Ronald Breslow’s group at Columbia, they designed and synthesized a series of molecules to use in the experiment.

“Reliably making a circuit from a single molecule is really challenging,” says Latha Venkataraman, a Columbia Engineering Applied Physics professor whose group perfected the method used to make the molecular circuits. “Imagine trying to touch the two ends of a molecule that is only ten atoms long.”

To make the circuits, Venkataraman’s group adapted a scanning tunneling microscope (STM) apparatus to repeatedly press a sharp gold tip into another gold electrode and then pull it away. When this junction breaks, there is a moment when the gap between the two pieces of gold is a perfect fit for the molecule. Once the circuit system is set up, the conductance measurement is fast and can be repeated thousands of times to get statistically reliable data.

Using this approach, the scientists discovered that the molecules with two built-in pathways like the one visualized in the figure at right had a conductance that was greater than the sum of each arm’s conductance, although the increase was not as large as they had anticipated. In order to understand this effect better, Columbia’s Hector Vasquez worked with Hybertsen to computationally simulate the quantum mechanical transmission of an electron through each circuit.

“Both the measurements and the simulations show that the molecules with two parallel paths can have a conductance that is bigger than two times that of molecule with a single path,” said Hybertsen. “This is the signature that the quantum interference effect is playing a role.”

The group suspects that other factors, such as the nature of the molecule’s bond to the electrodes, need to be considered when calculating the conductance of a molecular circuit. They are currently looking into other central questions about molecular electronics, including how the device changes when different metals are used. 

This research was funded primarily by the National Science Foundation and the New York State Office of Science, Technology, and Academic Research. Columbia’s Rachid Skouta and Severin Schneebeli synthesized the experiment molecules with Ronald Breslow and Masha Kamanetska carried out the conductance measurements. The CFN at Brookhaven Lab is supported by the DOE’s Office of Science. ""

Refs: brough to my attention by:

MaterialsToday in their article entitled "Electronics, at the molecular scale"

"06 September 2012.