Hypergravity helping aircraft fly further

Nov 06, 2012
Aircraft turbine in flight. ESA research has helped to develop an aircraft-grade alloy that is twice as light as conventional nickel superalloys while offering equally good properties. Credit: Creative Commons–A. Rueda

(Phys.org)—ESA research has helped to develop an aircraft-grade alloy that is twice as light as conventional nickel superalloys while offering equally good properties. The path to creating this alloy required research under all types of gravity.

Airlines are always looking for ways to save fuel by cutting down on weight without sacrificing safety. Generally, cutting weight by 1% will save up to 1.5% in fuel.

For , this saving quickly adds up, offering cheaper flights and fewer stopovers while reducing the overall impact on the environment.

For years, engineers have known that titanium aluminide alloys offer great weight benefits over the nickel superalloys used today in conventional .

This video is not supported by your browser at this time.

Since the newer alloy can withstand up to 800°C, it is of particular interest to engine manufacturers.

Although it is possible to make the alloy in a laboratory, casting it in the shapes required by industry, such as a turbine blade, is not simple.

ESA scientists working in the Impress project looked into the problem. To understand natural processes, scientists often remove as many external variables as possible, concentrating their observations on core interactions.

The Impress project needed to 'switch-off' a factor that hampers observations: .

Aircraft turbine. ESA research has helped to develop an aircraft-grade alloy that is twice as light as conventional nickel superalloys while offering equally good properties. Credit: Creative Commons–Bleuchoi

Switching off gravity

Aluminium samples were heated in a small carried in a launched from Kiruna, Sweden. During six minutes of free fall, they were heated to over 700°C and then monitored by X-rays as they cooled.

Looking at the results, the researchers realised that casting titanium aluminides might require looking in the opposite direction: hypergravity. 

ESA is the only organisation that offers all levels of gravity, so the Impress team turned to the agency's centrifuge in the ESTEC research and technology centre, the Netherlands to test their theory.

The Large Diameter Centrifuge (LDC) at ESA's European Space Research and Technology Centre (ESTEC) at Noordwijk in the Netherlands.

Casting the metals in a creating up to 20 times normal gravity helps the liquid metals to fill every part of a mould, producing a perfectly cast alloy, even with complex shapes.

Analysing metal casting in as many ways as possible produced building blocks of knowledge that allowed the industrial process to be refined and commercialised.

Over a million jet turbine blades will be made over the next eight years, and using titanium aluminide would reduce their weight by 45% over traditional components.

The alloy's benefits are also of interest to the car industry – before long, cars will run on engines using space-based knowledge.

Explore further: LiquidPiston unveils quiet X Mini engine prototype

Related Stories

Hydrogen tank lighter than battery

Nov 04, 2008

Dutch-sponsored researcher Robin Gremaud has shown that an alloy of the metals magnesium, titanium and nickel is excellent at absorbing hydrogen. This light alloy brings us a step closer to the everyday use of hydrogen as ...

Shape memory materials ready for mass production

Sep 23, 2011

Five years ago, Professor Mirko Gojic, a researcher at the University of Zagreb in Croatia, wondered what his small team of researchers could do to lower the price of 'smart metals': a type of high-tech materials that can ...

Japanese material scientists develop new superelastic alloy

Jul 01, 2011

(PhysOrg.com) -- Working out of Tokyo University, scientists in the Department of Materials Science, have developed a new metal alloy that unlike other “superelastic” alloys can resume its original shape in temperatures ...

Recommended for you

LiquidPiston unveils quiet X Mini engine prototype

Nov 21, 2014

LiquidPiston has a new X Mini engine which is a small 70 cubic centimeter gasoline powered "prototype. This is a quiet, four-stroke engine with near-zero vibration. The company said it can bring improvements ...

Novel robotic walker helps patients regain natural gait

Nov 21, 2014

Survivors of stroke or other neurological conditions such as spinal cord injuries, traumatic brain injuries and Parkinson's disease often struggle with mobility. To regain their motor functions, these patients ...

Tomorrow's degradable electronics

Nov 20, 2014

When the FM frequencies are removed in Norway in 2017, all old-fashioned radios will become obsolete, leaving the biggest collection of redundant electronics ever seen – a mountain of waste weighing something ...

User comments : 14

Adjust slider to filter visible comments by rank

Display comments: newest first

Valentiinro
5 / 5 (3) Nov 06, 2012
45% weight reduction on a vital part? That's great!

It sounds pretty expensive though, since you have to cast it in a powerful centrifuge.
indio007
3.4 / 5 (10) Nov 06, 2012
Now all they have to do is make the centrifuge out of the same material and they will save even more money.
maxb500_live_nl
3 / 5 (3) Nov 06, 2012
45% weight reduction. That`s very impressive. I love that image of the ESA Large Diameter Centrifuge in the Netherlands.
Mike_Massen
3 / 5 (8) Nov 06, 2012
Centrifugal castings have been used for many years, not that much more expensive for the needed quality. It would be of interest to know in which direction the gravity gradient is oriented in comparison with the forces on the blade when in use etc

Would also be interesting to gauge a further speculative comparison of woven metal/graphine composite sintered in such an environment, another 20% reduction in weight perhaps ?

We are certainly gravitating (nominally) to increased understanding of materials... :-)
El_Nose
2.6 / 5 (5) Nov 06, 2012
all that is needed now is the combined weight of the turbine blades to aircraft weight.

Now if its less than 0.5% then this is very superficial
Husky
4.2 / 5 (5) Nov 06, 2012
all the tiny superficial things combined add up, here are the numbers on what GE achieved with ceramic matrix blades:

"Taking two-thirds out of the weight of a set of turbine blades means you have a lot less turbine structure," Carlson says. "That translates into smaller shafts, smaller bearings. It allows the design to improve all areas of the engine."

GE has estimated that incorporating CMC turbine blades on a GE90-sized engine could reduce the overall weight by about 455kg (1,000lb), which represents about 6% of 7,550kg dry weight of the full-sized GE90-115.
gwrede
1 / 5 (3) Nov 06, 2012
It would be of interest to know in which direction the gravity gradient is oriented in comparison with the forces on the blade when in use etc
An aircraft turbine blade consists of the blade part and the stem part. The latter attaches it to the engine shaft. (It's more complicated than that, but suffices here.) The blade part is simple in form, whereas the "root" part has a very complicated geometry, where metal really needs to fill small complicated crevices.

Therefore we can assume that the blade's orientation with regard to acceleration when cast is with the blade "up" and root "down". Which is the opposite of when the blade is in use. There it "hangs" from the root.
Isaacsname
not rated yet Nov 06, 2012
Couldn't they achieve the same thing with vacuum casting ?
PPihkala
1 / 5 (2) Nov 07, 2012
How about doing the casting underwater? Air pressure at 100m underwater would be 10x normal and one can go deeper if that is not enough. That environment would probably need all-automated production, but one could cast as big parts one wants without centrifuge size limitations. If air pressure is helpful then pressure chamber could also be the answer.
maxb500_live_nl
3 / 5 (3) Nov 07, 2012
PPihkala you can`t do that without exposing the material to the water itself. It would mix with the water and be useless.
Mike_Massen
2.3 / 5 (6) Nov 08, 2012
Dont people read comments, centrifugal casting has been around for years, its energy efficient, precise, easy to control with many possible settings, rise/fall times etc and not particularly expensive.
mrlewish
not rated yet Nov 09, 2012
45% weight reduction on a vital part? That's great!

It sounds pretty expensive though, since you have to cast it in a powerful centrifuge.


Yes like the 100 g's that typical washing machine can do.
MikeGroovy
1 / 5 (1) Nov 09, 2012
"Hypergravity" in the title first made me think this was about something theoretical. Hopefully this process will be cheap and can be applied in other industries. How many more breakthroughs are we going to need before we get flying cars? Could this be light enough to be make a practical hybrid a Jet propulsion engine (for use while in the atmosphere and then later kick on an upper rocket stage?)
georgejmyersjr
not rated yet Nov 28, 2012
Maybe they could use the one in Warminster, PA though billed as the "human centrifuge". I recall there was one in Buffalo, NY also.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.