Abstract

A novel method has been developed for nondestructively determining the thermal inertia (k_ρC_p) of solids near room temperature. The method involves heating, with radiant energy, for a short time a small area on the surface of a solid whose dimensions are such that it appears semi-infinite during this period. Simultaneously, the characteristically shaped temperature rise of the central region of this area is observed using an ir radiometer as the sensor. A comparison of this history with that for a reference standard yields the local thermal inertia value. The localized thermal conductivity and diffusivity can then be determined if the density and specific heat are known. Present technique precision for good conductors is slightly less than that for destructive measuring techniques.

© 1968 Optical Society of America

Principles and Applications of Emittance-Independent Infrared Nondestructive Testing

Donald R. Green
Appl. Opt. 7(9) 1779-1789 (1968)

Test measurements of the photothermal deflection method to determine the thermal diffusivity of solids

Giovenna Suber, Mario Bertolotti, Concita Sibilia, and Aldo Ferrari
Appl. Opt. 27(9) 1807-1810 (1988)

Evaluation of Bonds in Armor Plate and Other Materials Using Infrared Nondestructive Testing Techniques

Paul E. J. Vogel
Appl. Opt. 7(9) 1739-1742 (1968)

Procedures for Determining the Spectral Responsivity of an Infrared Radiometer

W. E. Schneider and J. A. Garvey
Appl. Opt. 7(6) 1141-1148 (1968)

Experimental Measurements of Thermal Radiation Properties by Cyclic Incident Radiation

Ernie W. Spisz and John R. Jack
Appl. Opt. 7(11) 2259-2263 (1968)