Subscribe free to our newsletters via your
. 24/7 Space News .




TECH SPACE
Research could improve laser-manufacturing technique
by Staff Writers
West Lafayette, IN (SPX) Dec 21, 2011


This series of high-speed images shows how plasma expands when material is exposed to ultrafast laser pulses. Purdue researchers have discovered details that could help to harness the technology for applications in manufacturing, diagnostics and research. (Yung Shin, Purdue University School of Mechanical Engineering). For a larger version of this image please go here.

Engineers have discovered details about the behavior of ultrafast laser pulses that may lead to new applications in manufacturing, diagnostics and other research.

Ultrafast laser pulses are used to create features and surface textures in metals, ceramics and other materials for applications including the manufacture of solar cells and biosensors.

The lasers pulse at durations of 100 femtoseconds, or quadrillionths of a second, and cause electrons to reach temperatures greater than 60,000 degrees Celsius during the pulse duration. The pulses create precise patterns in a process called "cold ablation," which turns material into a plasma of charged particles.

Images taken with a high-speed camera show tiny mushroom clouds eerily similar in appearance to those created in a nuclear explosion. The clouds expand outward at speeds of 100 to 1,000 times the speed of sound within less than one nanosecond.

However, new findings reveal that an earlier cloud forms immediately before the mushroom cloud, and this early plasma interferes with the laser pulses, hindering performance, said Yung Shin, a professor of mechanical engineering and director of Purdue University's Center for Laser-Based Manufacturing.

Finding a way to eliminate the interference caused by the early plasma could open up new applications in manufacturing, materials and chemical processing, machining and advanced sensors to monitor composition, and chemical and atomic reactions on an unprecedented scale, he said.

Researchers used experiments and simulations to study the phenomenon. Research papers about the work were published online Dec. 6 in Applied Physics Letters and in September in the journal Physics of Plasmas. The papers were written by doctoral student Wenqian Hu, Shin and mechanical engineering professor Galen King.

"We found the formation of early plasma has very significant bearing on the use of ultrashort pulse lasers because it partially blocks the laser beam," Shin said. "The early plasma changes the optical properties of air, but the mechanism is still largely unknown."

The researchers studied the early plasma by tracking the movement of millions of individual atoms in the plasma; observing how the laser beam travels in space and interacts with plasma; and using a "laser pump probe shadowgraph," a technique in which one laser ablates a material, producing the early plasma, and a second laser fired perpendicular to the first is used to study the cloud. A series of optical elements and mirrors is used in the shadowgraph technique.

Abstract on the research in this release can be found here.

.


Related Links
Purdue University
Space Technology News - Applications and Research






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








TECH SPACE
New Light Cast on Electrons Heated to Several Billion Degrees By Lasers
Dresden, Germany (SPX) Nov 29, 2011
A new class of high power lasers can effectively accelerate particles like electrons and ions with very intense, short laser pulses. This has attracted the interest of researchers around the globe, working out the details of the acceleration process which occurs when a laser beam impinges on a thin foil to accelerate ions from the foil's rear surface to high energies. The electrons in the ... read more


TECH SPACE
Peres promotes Israeli moon probe

Hundreds of NASA's moon rocks missing: audit

Schafer Corp Signs Licensing Agreement with MoonDust Technologies

Russia wants to focus on Moon if Mars mission fails

TECH SPACE
Meteorite Shock Waves Trigger Dust Avalanches on Mars

Opportunity at One of its Two Winter Spots

Scientists find microbes in lava tube living in conditions like those on Mars

MARSIS Completes Measurement Campaign Over Martian North Pole

TECH SPACE
Astrophysicist John Grunsfeld to Head NASA Science Directorate

A Brighter Future for Spaceflight

Goddard Scientists Selected as Participating Scientists in Mars Lab and Cassini Missions

Mankind faces long road in space exploration

TECH SPACE
Tiangong-1 orbiter starts planned cabin checks against toxic gas

China celebrates success of space docking mission

Two and a Half Men for Shenzhou

China honors its 'father' of space efforts

TECH SPACE
Russia sends multinational crew to ISS

As Soyuz Rolls ISS Crew Work On Science

ESA astronaut Andre Kuipers Ready For Launch To ISS

Astronaut TJ Creamer Learns Space Station Science From the Ground Up

TECH SPACE
Next ESA Astronaut Ready For Launch As Soyuz Rolls Out

Acra Control Proven in Low Earth Orbit

Vega moves closer to its first liftoff

Arianespace Signs First launch contracts for Vega

TECH SPACE
NASA Discovers First Earth-size Planets Beyond Our Solar System

First Earth-sized planets found

Earth-sized worlds spotted in new advance for exoplanets

Giant Super-Earths Made Of Diamond Are Possible

TECH SPACE
Canada hunts for rare earth metals as China cuts back

Split decision in Microsoft smartphone patent case

Hollywood still struggling to focus 3D technology

Research could improve laser-manufacturing technique




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement