The "Holy Grail" of nanotechnology is to make thin sheets of "paper" out of
carbon nanotubes. Then the sheets can be laminated together to form things
like aircraft wings, etc.
It looks like they are on to something at FSU - <http://tinyurl.com/69tnnr
I wonder how it machines?
I also remember reading an article about how they think nanotubes might
cause mesothelioma (asbestos related) type cancers.
That could be a relevant question for machinists in the near future as
literally TONS of carbon nanotubes (CNT's), are now being manufactured.
CNTs today are available for industrial applications in bulk
quantities up metric ton quantities from Cheap Tubes. Several CNT
manufacturers have >100 ton per year production capacity for multi
I have seen forecasts predicting that GM alone will consume over 500
tons of CNT masterbatches in 2006 for using in all areas of automotive
There are many useful and unique properties of CNTs.
The list includes:
High Electrical Conductivity
Very High Tensile Strength
Highly Flexible- can be bent considerably without damage
Very Elastic ~18% elongation to failure
High Thermal Conductivity
Low Thermal Expansion Coefficient
Good Field Emission of Electrons
High Aspect Ratio (length = ~1000 x diameter)
Possibly more important than fullerenes are Carbon nanotubes, which
are related to graphite. The molecular structure of graphite resembles
stacked, one-atom-thick sheets of chicken wire - a planar network of
interconnected hexagonal rings of carbon atoms. In conventional
graphite, the sheets of carbon are stacked on top of one another,
allowing them to easily slide over each other. That is why graphite is
not hard, but it feels greasy, and can be used as a lubricant. When
graphene sheets are rolled into a cylinder and their edges joined, they
form CNTs. Only the tangents of the graphitic planes come into contact
with each other, and hence their properties are more like those of a
molecule. ["Nanotechnology: Basic Science and Emerging Technologies" M.
Wilson et al, (2002)]
A nanotube may consist of one tube of graphite, a one-atom thick
single-wall nanotube, or a number of concentric tubes called
=========================================================== Back to realtime here; Now since the article above states that CNT's
are essentially rolled up sheets of graphite, I would "speculate" that
the machining forces needed to turn or mill CNT's would be similar to
machining planar graphite.
Perhaps, perhaps not. Not having a sample to play with I can't really
'Carbon nanotubes introduced into the abdominal cavity of mice show
asbestos-like pathogenicity in a pilot study' was authored by
scientists at MRC/University of Edinburgh, School of Materials,
University of Manchester, Woodrow Wilson International Center for
Scholars, Washington DC, Institute of Occupational Medicine, Edinburgh
and School of Life Sciences, Edinburgh.
The report abstract says:
Carbon nanotubes have distinctive characteristics, but their
needle-like fiber shape has been compared to asbestos, raising concerns
that widespread use of carbon nanotubes may lead to mesothelioma,
cancer of the lining of the lungs caused by exposure to asbestos.
Here we show that exposing the mesothelial lining of the body cavity
of mice, as a surrogate for the mesothelial lining of the chest cavity,
to long multiwalled carbon nanotubes results in asbestos-like,
length-dependent, pathogenic behavior. This includes inflammation and
the formation of lesions known as granulomas. This is of considerable
importance, because research and business communities continue to
invest heavily in carbon nanotubes for a wide range of products5 under
the assumption that they are no more hazardous than graphite. Our
results suggest the need for further research and great caution before
introducing such products into the market if long-term harm is to be
======================================================== Reading the above, I don't think I even WANT a sample to play with. LOL
I remember reading something just like what you posted and every time I
read some new news about CNT's I can't help but think it's all going to
end badly for the companies involved. The asbestos litigation tanked a
bunch of big companies.
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