12-09-2012, 04:01 PM
Nanotechnology in Aerospace Applications
1Nanotechnology.pdf (Size: 186.14 KB / Downloads: 85)
ABSTRACT
The aerospace applications for nanotechnology include high strength, low weight composites, improved
electronics and displays with low power consumption, variety of physical sensors, multifunctional materials
with embedded sensors, large surface area materials and novel filters and membranes for air purification,
nanomaterials in tires and brakes and numerous others. This lecture will introduce nanomaterials
particularly carbon nanotubes, and discuss their properties. The status of composite preparation – polymer
matrix, ceramic matrix and metal matrix – will be presented. Examples of current developments in the above
application areas, particularly physical sensors, actuators, nanoelectromechanical systems etc. will be
presented to show what the aerospace industry can expect from the field of nanotechnology.
Of all the nanoscale materials, carbon nanotubes (CNTs) have received the most attention across the world.
These are configurationally equivalent to a two-dimensional graphene sheet rolled up into a tubular structure.
With only one wall in the cylinder, the structure is called a single-walled carbon nanotube (SWCNT).
The structure that looks like a concentric set of cylinders with a constant interlayer separation of 0.34 A is
called a multiwalled carbon nanotube (MWCNT).
The CNT’s structure is characterized by a chiral vector (m, n). When m-n/3 is an integer, the resulting
structure is metallic; otherwise, it is a semiconducting nanotube. This is a very unique electronic property that
has excited the physics and device community leading to numerous possibilities in nanoelectronics. CNTs also
exhibit extraordinary mechanical properties. The Young’s modulus is over 1 TPa and the tensile strength is
about 200 GPa. The thermal conductivity can be as high as 3000 W/mK. With an ideal aspect ratio, small tip
radius of curvature and good emission properties, CNTs also have proved to be excellent candidates for field
emission. CNTs can be chemically functionalized, i.e. it is possible to attach a variety of atomic and molecular
groups to the ends of sidewalls of the nanotubes.
The impressive properties alluded above have led to investigations of various applications. The most
important aerospace application is high strength, low weight composites. Investigation of metal and ceramic
matrix composites with CNTs as a constituent materials is in its infancy. A status update will be provided.
CNTs have been shown to provide desirable electrical properties for polymer matrix composites. In many
cases, the current problem is the inability to disperse the nanotubes homogeneously across the host matrix.
1Nanotechnology.pdf (Size: 186.14 KB / Downloads: 85)
ABSTRACT
The aerospace applications for nanotechnology include high strength, low weight composites, improved
electronics and displays with low power consumption, variety of physical sensors, multifunctional materials
with embedded sensors, large surface area materials and novel filters and membranes for air purification,
nanomaterials in tires and brakes and numerous others. This lecture will introduce nanomaterials
particularly carbon nanotubes, and discuss their properties. The status of composite preparation – polymer
matrix, ceramic matrix and metal matrix – will be presented. Examples of current developments in the above
application areas, particularly physical sensors, actuators, nanoelectromechanical systems etc. will be
presented to show what the aerospace industry can expect from the field of nanotechnology.
Of all the nanoscale materials, carbon nanotubes (CNTs) have received the most attention across the world.
These are configurationally equivalent to a two-dimensional graphene sheet rolled up into a tubular structure.
With only one wall in the cylinder, the structure is called a single-walled carbon nanotube (SWCNT).
The structure that looks like a concentric set of cylinders with a constant interlayer separation of 0.34 A is
called a multiwalled carbon nanotube (MWCNT).
The CNT’s structure is characterized by a chiral vector (m, n). When m-n/3 is an integer, the resulting
structure is metallic; otherwise, it is a semiconducting nanotube. This is a very unique electronic property that
has excited the physics and device community leading to numerous possibilities in nanoelectronics. CNTs also
exhibit extraordinary mechanical properties. The Young’s modulus is over 1 TPa and the tensile strength is
about 200 GPa. The thermal conductivity can be as high as 3000 W/mK. With an ideal aspect ratio, small tip
radius of curvature and good emission properties, CNTs also have proved to be excellent candidates for field
emission. CNTs can be chemically functionalized, i.e. it is possible to attach a variety of atomic and molecular
groups to the ends of sidewalls of the nanotubes.
The impressive properties alluded above have led to investigations of various applications. The most
important aerospace application is high strength, low weight composites. Investigation of metal and ceramic
matrix composites with CNTs as a constituent materials is in its infancy. A status update will be provided.
CNTs have been shown to provide desirable electrical properties for polymer matrix composites. In many
cases, the current problem is the inability to disperse the nanotubes homogeneously across the host matrix.