The effect of humidity on nanomechanical and nanotribological properties can be significant for certain classes of materials. There will be some degree of property-altering humidity effects on every material that can adsorb moisture. For example, in polymeric systems adsorbed moisture can interfere with molecular chain bonding and cause swelling of the material. In thin films, water adsorption leads to volume expansion, resulting in increased film stresses and altered mechanical and interfacial properties. Additionally, materials that do not readily adsorb moisture, such as ceramics, may display altered fracture toughness values as a function of humidity level. Testing moisture-sensitive materials under well-controlled humidity conditions is essential for reliable property measurements.
Bruker’s atmospheric control technologies allow humidity control capabilities from dry to condensing conditions. Humidity control can be combined with the majority of Bruker’s Hysitron testing techniques to achieve a thorough understanding of quantitative nanoscale-to-microscale mechanical and tribological properties at well-defined humidity levels.