Two-points pulsed thermal diagnostics of thin film materials

Thin films and film coatings, wide-used in different branches of modern technique and technology (from electronics up to rocket design), are too inconvenient for thermal nondestructive testing. The conventional front-face-flash methods, which are the most suitable for these purposes, have time limitation derived from relation between a response time of a measuring system (t_d) and a characteristic time of an investigated object 4^.t_d<4.43^. 10^-3 L²/α, (1) where L-the thickness of object, α-the thermal diffusivity. It follows from (1) that, if we refuse from a traditional temperature measuring directly at the pulsed heating region and measure the temperature at any distance "r_*" from the center of the heating spot with radius "R", we\´ll have as a characteristic dimension not "L" but "r_*", which can be varied, so excluding the limitation (1). In this case under R>L, r_*>10^.R, r_*>2L, when measuring the temperature at the time moment "τ" (at the inflection point of the temperature response curve), we can obtain the simple relation to calculate the thermal diffusivity α=0.042^.r _*²/τ. This method does not need specific instrumentation and is very easy for realization