| About this Abstract |
| Meeting |
Materials Science & Technology 2011
|
| Symposium
|
Recent Advances in Structural Characterization of Materials
|
| Presentation Title |
Microscopic Surface Mapping of the Thermal Diffusivity by Photothermal Confocal Defocusing |
| Author(s) |
Oscar Eduardo Martinez, Nelida Mingolo, Ulises Crossa Archiopoli |
| On-Site Speaker (Planned) |
Oscar Eduardo Martinez |
| Abstract Scope |
A technique is presented that allows the microscopic surface mapping of the thermal diffusivity of materials and can be mounted as an accessory in an optical microscope. A modulated pump laser heats the sample and a perfectly coaxial probe laser measures the surface deformation due to the thermal expansion. The technique relies in the use of photonic technology to assemble the entire optical setup with optical fiber components. The system results extremely robust and perfectly aligned.. The dependence of the defocusing with the pump modulation frequency yields the thermal diffusivity of the sample at the impinging location. Surface and in depth profiles can be retrieved scanning at a single modulation frequency. Ceramics, glasses and metals are studied. In particular for surface treated steel a linear correlation of the inverse of the thermal diffusivity with the hardness allows a noncontact hardening mapping with microscopic resolution. |
| Proceedings Inclusion? |
Definite: A CD-only volume |