The scanning thermal conductivity microscope (STCM) is capable of producing two-dimensional thermal conductivity maps of specimen surfaces with sub-micron resolution. This instrument is based on an atomic force microscope with a probe modified to measure thermal conductivity. The temperature of the probe is elevated slightly above that of the test specimen. When the probe tip is brought into contact with the test specimen, the probe tip will cool. The amount by which the probe will cool is related to the thermal conductivity of the test specimen in the region of contact. The probe is located at the end of a long, thin cantilever, which is rastered across the surface of the test specimen by means of piezoelectric translators. Topographic information comes from the voltage applied to the Z-piezoelectric stack; simultaneously, thermal conductivity contrast information comes from the bolometer located on the warmed probe. The topographic and conductivity information is associated with a position on the specimen surface through the voltages applied to the X- and Y-piezoelectric stacks. This provides a means of visually correlating thermal conductivity variations with microstructural features. The thermal conductivity probe is calibrated by using standard reference materials and high-purity materials.

Features:

• Produces topographic and thermal conductivity images simultaneously
• Measures relative room-temperature thermal conductivity with sub micron resolution
• Maps functionally gradient coatings, composites, intergranular phases, powders, fibers, thin films, metals, ceramics, glasses, superconductors, etc.
• Complete computer control of data acquisition
• Easy to learn menu-driven data acquisition and image analysis software
• Short measurement time

Applications:

Microscopic thermal conductivity studies provide a better understanding of bulk thermal conductivity studies and enable studies of microscopic structures that are difficult or impossible to accurately characterize with traditional techniques. Simultaneous topographic and thermal conductivity contrast images will allow visual correlation between thermal conductivity and microstructural features. The STCM can also study the post-processed constituent properties of composite materials. This furnishes valuable information on the effect that processing, environmental exposure, and thermomechanical history have on the thermal conductivity of materials.