Aluminium Nanotube Alloy Fabricated by Bayer

Assuming huge volumes of cheap nanotubes are plausibly producible, then metallurgy will be changed forever. Here we are talking about the obvious one combining the nanotubes with aluminum. The results are excellent. The next obvious one is titanium.

I even posted on this a few months back as a likely prospect and it is good to see that it is standing up to fabrication.

Little is said yet about machining and all that, but it may make titanium easier to work with. We shall see.

They talk about tall buildings but that is actually a small bit of the future market, if any at all. Jet engines are almost certainly a first application as they get lighter and hotter. A step behind will be rocket engines for the same reasons.

The speed of development is presently breathtaking. Perhaps long fibers are close.

Baytubes® carbon nanotubes enhance the properties of aluminum: Nearly as strong as steel, but half as heavy

Partnership between Bayer MaterialScience, Alcan, PEAK and Zoz

June 4, 2009

Pittsburgh, June 4, 2009 — The addition of Baytubes® carbon nanotubes (CNT) from Bayer MaterialScience AG significantly improves the mechanical properties of aluminum powder metallurgy. For example, the hardness of the composite aluminum is then several times greater than that of unalloyed aluminum, tensile strengths comparable to those of steel can be achieved, and the impact strength and thermal conductivity of the lightweight metal can be improved significantly. "Together with competent partners in industry, we want to exploit the considerable application potential that arises from this optimization in properties," says Dr. Horst Adams, vice president of Future Technologies at Bayer MaterialScience, explaining: “We are partnering with Alcan, PEAK and Zoz to develop customized, CNT-reinforced aluminum materials."

Based in Montreal (Quebec), Canada, Alcan Inc. is not only one of the world's largest suppliers of raw materials for aluminum manufacturing, it also is a leading producer of this lightweight metal and products made from it. PEAK Werkstoff GmbH, headquartered in Velbert, Germany, specializes in the development of high-performance aluminum materials, which it uses to produce powder metallurgy semi-finished and finished goods. Zoz GmbH based in Wenden, Germany, is a global supplier of innovative facilities and equipment, in particular for the production of nanostructured materials, and has comprehensive expertise, for example, in the high-energy milling and mechanical alloying of these materials.

Until now, high hardness levels and tensile strengths could only be achieved in aluminum by a complex alloying process based on rare and expensive metals. "Our carbon nanotubes are an attractive alternative to such complicated alloys. Baytubes® carbon nanotubes can also significantly reinforce aluminum materials already alloyed with metals," says Adams.

The density of CNT-reinforced aluminum is only around one third that of steel. Therefore, the material can be used in any number of applications in which the goal is to reduce weight and energy consumption. With its combination of high strength and low weight, Baytubes®-reinforced aluminum is a welcome alternative to steel, expensive specialty metals such as titanium, and carbon-fiber-reinforced plastics.

"This new class of materials has great potential for the production, for example, of screws and other connecting elements, allowing existing manufacturing processes (stamping, CNC) to be retained. Lightweight, heavy-duty components for wheelchairs or athletic equipment are also ideal candidates for the material," says Adams. Promising applications exist too in the automotive and aircraft industries. In addition, Baytubes®-reinforced aluminum I-beams could conceivably be manufactured for the construction industry. Because they are much lighter than steel I-beams, they could make it possible to construct taller buildings. Because of their inherent weight, steel I-beams currently are a factor limiting the maximum height of a skyscraper.

Bayer MaterialScience LLC is one of the leading producers of polymers and high-performance plastics in North America and is part of the global Bayer MaterialScience business with nearly 15,100 employees at 30 sites around the world and 2008 sales of 9.7 billion euros. Business activities are focused on the manufacture of high-tech polymer materials and the development of innovative solutions for products used in many areas of daily life. The main segments served are the automotive, electrical and electronics, construction, medical, and sports and leisure industries.

For more information about Bayer MaterialScience's Baytubes® carbon nanotubes, call 412-777-3983, e-mail naftainfo@bayerbms.com or visit

www.bayermaterialsciencenafta.com or www.baytubes.com.

Space Elevator Considerations

I still am startled that it is possible to discuss a space tether as a possibility. Thirty years ago, all calculations merely underlined the sheer impossibility. Now we get to worry about the need to make improved electrical motors. We are now discussing problems that we believe can be resolved sooner or later.

This is putting numbers on paper that allows one to go deeper into design issues.

We need to produce a fabricating device that produces a fiber made from nested carbon nanotubes. We have them in the lab. Continuous production is quite a trick but one that at least sounds solvable. A bundle of such fibers would make an excellent tether material that we all believe in. Flaw testing should be as simple as sending current down the tubes.

While we are at it, that current could handily drive a simple mechanism that causes the lifting craft to spin around the tether. If the craft then had short wings, it would be able to auger in and out of the lower atmosphere, which is the most difficult part of the trip. It would be a lousy ride for a human being but a definite way to accommodate large tonnage lifting needed for near space manufacturing while lowering the load on the tether itself.


Current Space Elevators Tether Expectations and Engine Power Density

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEguAU0e41uRBqF3cg6bWpQncdmk_aycp1n_0oMGMiPOgiOpFdFrk_9_eAYd-nQatPRikJZXRgqKc3noEwmWZBD2IFYEewQvdHm8Osw3n08jkr5-lNzpL8GOsEzkEzID9VO-EUpNZ-xHwkk/s1600-h/spaceelevatorfeasible.JPG


Spaceward has a page on space elevator feasibility that looks at tether strength and power to weight ratio for the power system for the space elevator climber.

Based on a gradual convergence of experimental and theoretical results, the specific strength of raw CNTs will not exceed 50 MYuri [1 Mega-Yuri = 1 N/Tex = 1 GPa-cc/g]. A failure mechanism known as the Stone-Wales causes spontaneous defects in the Nanotube structure and limits the possible strength. Using 45-50 MYuri CNTs, we can expect a near-flawless spun tether to perform at 40 MYuri, and with a 33% safety margin, we can load the tether at a TSL of 30 MYuri.

Reaching a power mass density of 1.5 – 2.5 kWatt/kg is difficult. The best electric motors today achieve just under 1.5 kWatt/kg, leaving no margin for the PV panels. In order for the complete power system to reach 1.5 kWatt/kg, electric motor weight needs to be reduced by a factor of at least 2

Assuming extropolated technology space elevators are still feasible but space elevators are pushing what might be possible on several levels.

Graphene Hydride

Do take a look at this image. I almost got excited until I realized that no one had actually made this yet. The only improvement over speculations that I made on exactly this type of carbon structure thirty years ago is that they have shown that it is theoretically stable and possibly workable.

Carbon wonderfully lends itself to this type of theoretical construction. It is your atom of choice if you have an active imagination. It is also proving to be magical when we can actually make something like a very small sheet of graphene.

Research is in full swing and I look forward to someone been able to actually fabricate a three dimensional graphene structure just to store hydrogen. Recall that a serious effort went into the development of metal hydrides thirty years ago for the same reason and that they were a lot easier to fabricate.

Obviously a container holding small pellets would sponge huge amounts of hydrogen into the structure eliminating gas pressure, or at least managing it. This promises to be a light weight method of storing a large amount of hydrogen and well worth the effort.

Designing novel carbon nanostructures for hydrogen storage

http://spie.org/x33929.xml?highlight=x2400&ArticleID=x33929

George Dimitrakakis, George Froudakis, and Emmanuel Tylianakis

Pillared graphene provides a stable architecture for enhanced fuel storage.

9 March 2009, SPIE Newsroom. DOI: 10.1117/2.1200902.1451

Energy consumption has reached record levels, and global demand is expected to grow by more than half over the next quarter of a century. The greenhouse effect and global warming are only two of the issues we face. In addition, fossil fuel reserves are gradually being depleted. To address these problems, we need a new, clean energy source. Hydrogen is an ideal environmentally friendly energy carrier, since the only product from its combustion is water. The main drawback limiting its wide use is the lack of an efficient storage device.

The United States Department of Energy (DOE) has established targets1 to be met by 2010 in order to use hydrogen as a fuel for mobile applications. Nanoporous carbon materials, like carbon nanotubes (CNTs),2 were initially considered ideal candidates for hydrogen storage.3–5 However, later work showed that pristine CNTs cannot store sufficient amounts of hydrogen under ambient conditions.6–8 On the other hand, doping CNTs with lithium atoms can considerably increase their capacity.9–11 Efficient storage also requires a material with high surface area and suitable pores.12,13 To fulfill these requirements, we designed pillared graphene.14
As shown in Figure 1, pillared graphene14 is the combination of two allotropes of carbon, CNTs and graphene sheets. The entire structure looks like a building in the early stages of construction, with CNTs forming the pillars and graphene sheets forming the floors. The combined 3D material has tunable pores, in which the length, width, and intertube distance of the CNTs can be changed at will. Tunable porosity is crucial for efficient hydrogen storage.

http://spie.org/Images/Graphics/Newsroom/Imported/1451/1451_fig1.jpg