ORLANDO, FL, August 2011 — Noted GE aviation consultant engineer Todd Rockstroh will be a featured speaker at the Laser Institute of America’s (LIA) inaugural Lasers for Manufacturing Event (LME) in September, detailing how lasers have steadily been asked to perform more intricate aviation production tasks over the past three decades.
Among the topics Rockstroh will address during his 30-minute educational session at LME will be the various applications of lasers in the manufacture of vital components of jet and gas-turbine engines. He will detail research that arose from — and solved — issues in the production and maintenance of jet-engine fans, compressors and combusters.
For example, he will detail the pivotal role high pulse energy lasers had in solving a critical operational issue afflicting the B1 bomber fleet in the 1990s. After intensive collaborative research, GE, the Air Force and Battelle Memorial Institute of Columbus, Ohio, found that laser shock processing (LSP) helped prevent damage to the leading edges of stage one fan blades by producing a deep compressive effect that halted the propagation of cracks. Previously, if a blade had been damaged on a mission, ground crews would have to crawl into each of the plane’s four engines to examine each blade of the stage one fans; the two-to-four-hour inspection could result in the plane being grounded up to three days while a replacement part was sought. LSP has dramatically lengthened the maintenance cycle.
In the 2000s, Rockstroh explains, the aviation industry embraced nanosecond and picosecond lasers when developers used them as part of the process of milling cooling holes in the complex shapes of advanced gas turbine blades. “GE has now installed over a dozen laser milling workstations into our supply chains,” he says.
As he notes in his presentation, the aviation industry adopted lasers in the 1980s as the most cost-effective way to drill shallow-angle holes in cast turbine superalloys. Ruby and Nd:YAG lasers drilled precise holes in seconds. Now, although holes for today’s better-performing engines are more often produced with electro-discharge drilling, lasers are still vital in making multihole aviation components like combustion liners and exhaust ducts. These parts require 10,000 to more than 100,000 holes. “Laser drilling is the only cost-effective means of producing high-volume output,” Rockstroh notes.
He will round out his presentation with a look at direct metal laser deposition of an upcoming gas turbine fuel circuit design. GE will test the additive-manufacturing technique, which uses metal powder, in 2012 with the intent of using it in full-scale production by 2014.
“Additive manufacturing is a huge opportunity for U.S. industries, defense and otherwise,” Rockstroh noted in a recent interview for the Laser Institute of America’s newsletter, LIA TODAY. “The Air Force has got it on their road map to start some larger programs in the ManTech realm.”
LME, to be held in Schaumburg, IL, on Sept. 27-28, is the first event of its kind, designed to feature a hands-on look at laser-manufacturing applications and equipment in a highly interactive setting showcasing the work of cutting-edge laser companies. For more information or to register to attend, visit www.LaserEvent.org.
Laser Institute of America (LIA) is the professional society for laser applications and safety serving the industrial, educational, medical, research and government communities throughout the world since 1968. LIA is the secretariat and publisher of the American National Standards Institute (ANSI) Z136 series of laser safety standards. For more information, visit www.lia.org.