Bonded aircraft

September 08, 2008

The lighter an aircraft is, the less fuel it consumes. Given the need to cut carbon dioxide emissions, this is a key aspect of materials research. Aircraft manufacturers are therefore pinning their hopes on particularly lightweight construction materials. These include not only lightweight metals, but also fiber composite plastics, particularly carbon-fiber reinforced plastics (CFRPs). Whenever two CFRP components have to be joined together, this has so far been accomplished primarily by riveting.

Researchers at the Fraunhofer Institute for Manufacturing Technology and Applied Materials Research IFAM in Bremen are experts in adhesive techniques and plan to enlarge their expertise to include mechanical joining. At the Composites Europe trade fair in Essen from September 23 through 25, 2008, they will be presenting a state-of-the-art C-clamp riveting machine (Hall 10-11, Stand 150). This device enables the necessary rivet holes, complete with one- or two-part riveted bolts, to be installed accurately and automatically in compliance with aviation standards.

The IFAM researchers now intend to go a step further. "Rivet holes are a problem, particularly in CFRP structures," explains Dr. Oliver Klapp of the IFAM. "They disturb the flow of forces in the CFRP structures and reduce the load-bearing capacity of the material." The researchers are therefore planning to make use of adhesive bonding processes that are already employed for CFRP materials. "But the aviation industry is not yet ready to rely exclusively on bonded components and assemblies," says Klapp. This is why the engineers are exploring the potential of hybrid joining - a combination of riveting and a special bonding process. The advantages of hybrid joining are obvious: the CFRP materials are not riddled with so many rivet holes. The particularly high load-bearing capacity of these materials is more effectively brought to bear in the truest sense of the word, because bonding results in a more effective, all-over distribution of forces. The researchers are currently optimizing the parameters of the joining process.

"It's true that riveting will not be eliminated from aircraft construction in the next several years," says Klapp. But the aviation industry will soon be unable to manage without structural bonding of primary structures such as the airframe, the wings and the tail units.
-end-


Fraunhofer-Gesellschaft

Related Aircraft Articles from Brightsurf:

University of South Carolina redefining aircraft production process
The University of South Carolina College of Engineering and Computing will transform the manufacturing and simulation processes used in aircraft production through a $5.7 million NASA grant.

Small altitude changes could cut climate impact of aircraft by up to 59%
Altering the altitudes of less than 2% of flights could reduce contrail-linked climate change by 59%, says a new Imperial study.

Small altitude changes could cut the climate impact of aircraft
Contrails -- the white, fluffy streaks in the sky that form behind planes -- can harm the environment.

New electrodes could increase efficiency of electric vehicles and aircraft
The rise in popularity of electric vehicles and aircraft presents the possibility of moving away from fossil fuels toward a more sustainable future.

Composite metal foam outperforms aluminum for use in aircraft wings
The leading edges of aircraft wings have to meet a very demanding set of characteristics.

Particulate matter from aircraft engines affects airways
In a unique, innovative experiment, researchers under the leadership of the University of Bern have investigated the effect of exhaust particles from aircraft turbine engines on human lung cells.

How to ice-proof the next generation of aircraft
To prevent ice formation on aircraft during flight, current systems utilize the heat generated by burning fuel, but these high-temperature, fuel-dependent systems cannot be used on the proposed all-electric, temperature-sensitive materials of next-generation aircraft.

Putting hybrid-electric aircraft performance to the test
Although hybrid-electric cars are becoming commonplace, similar technology applied to airplanes comes with significantly different challenges.

Aircraft microbiome much like that of homes and offices, study finds
What does flying in a commercial airliner have in common with working at the office or relaxing at home?

Sequential model chips away at mysteries of aircraft
Ice accumulation on aircraft wings is a common contributing factor to airplane accidents.

Read More: Aircraft News and Aircraft Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.