By Cameron Chai
Nano-composites and polymer nano-films are utilized in a broad range of
applications from packaging of food to sports equipment to aerospace and
automotive applications. Thermal analysis is performed regularly in order to
examine materials for these applications, but since nanostructured materials are
being commonly used, bulk methods are not suitable.
This is the atomic force microscope with an integrated heater actuated using Lorentz forces
In order to determine temperature dependent material characteristics at the
below-100 nm scale, nanoscale thermal analysis or nanoTA has been used in recent
years. nanoTA is highly effective for soft polymers. Researchers at Anasys
Instruments and the University of Illinois at Urbana-Champaign have demonstrated
that nanoTA can be performed on stiff materials such as filled composites and
epoxies.
According to the College of Engineering Bliss Professor in the Department of
Mechanical Science and Engineering at Illinois, by this innovative method, it is
possible to measure temperature as well as frequency-dependent material
characteristics at a high-speed over a broad bandwidth. A current is made to
flow around the U-shaped arms of the cantilever of a self-heating atomic force
microscope (AFM) and the current is made to interact with a magnetic field. The
tip-sample force is modulated near the AFM tip by the magnetic field.
According to the paper’s first author, Byeonghee Lee force control at the
nanometer scale can be achieved, which is not dependent on the heating
temperature.
According to co-author of the paper and CTO at Anasys Instruments, Craig
Prater, traditional nanothermal analysis involved highly crosslinked, highly
filled and below-100 nm thin films. This novel method has enabled consistent
measurement and mapping of melting and glass transitions on material groups that
were difficult before.
The paper is titled “Magnetic Actuation of a Heated Atomic Force Microscope
Cantilever using Lorentz Force" and was published in the Nanotechnology
journal.
Source: http://www.illinois.edu