Portland cement is the most common and widely used construction material and its
current production is estimated as 6 billion cubic meters per year [18]. The major
advantages of this material are: availability of raw materials for production all over the
world, low cost, room temperature setting, ease of construction, readily available
properties and performance data for design and construction. In addition modern day
concrete has a very good performance record for a period of more than 175 years.
Portland cement is typically used as cementing materials with fine and coarse aggregates
to create products that are a few mm to several meters thick. Average size of portland
cement particle is about 50 microns. In applications that require thinner final products
and faster setting time, micro cement with a maximum particle size of about 5 microns is
being used [10]. Therefore the particle size has to be reduced by an order of magnitude to
obtain nano-portland cement. If these nano-cement particles can be processed with nanotubes
and reactive nano-size silica particles; conductive, strong, tough and room
temperature processed ceramics can be developed both for electronic applications and
coatings. Since carbon oxidizes at temperatures above 400 °C, room temperature
processing will be a boon to retain the mechanical properties of carbon nano-tubes. Since
most ceramics are processed at temperatures much higher than 400 °C, carbon fibers can
not be used with these processes.