NRCtech participated in the EPFL - Solar Impulse collaboration by performing mechanical tests. Various samples of composite sandwiches were tested.

Laboratory tests can submit materials to known loads in order to measure their mechanical properties. With a four points bending test, we can obtain the following elements:

• Bending stiffness: the evolution of the deformation of a specimen as a function of the applied load allows to determine the bending stiffness,
• Values at break: when the tests are conducted to the failure of the specimen, it is possible to obtain the deformation and the load at break,
• Type of damage: in a composite material sandwich, the type of damage gives information about its critical areas.

The measurements were designed to compare two types of sandwiches built with different carbon fibers. These tests have established that a type of fiber provides significantly higher load and strain at break.