Nicoleta Cobîrzan

Complementary photothermal techniques for complete thermal characterization of porous and semi-transparent solids

The paper is focused on the ability of using two complementary photothermal techniques for the measurement of all thermal parameters of some porous and/or semi-transparent solid samples whose composition, structure, and geometry do not allow a complete thermal characterization using a single technique. In this work, we combine a contact technique, photopyroelectric (PPE) calorimetry, with a non-contact one, infrared lock-in IR thermography (IRT), in order to investigate some solid samples such as dental composites, building materials, drugs, and semiconductors. The composition and the geometry of the investigated samples make the PPE method (in “front” detection configuration together with thermal-wave resonator cavity (TWRC) technique as scanning procedure) suitable for thermal effusivity measurements and IRT for thermal diffusivity investigations. In such a way, this combination of methods leads to a complete thermal characterization of the investigated materials.