The photoacoustic model of multilayer with a strong-absorbing surface layer is developed. The phase of photoacoustic signal is measured as a function of modulated frequency using apparatus totally controlled by a comp...The photoacoustic model of multilayer with a strong-absorbing surface layer is developed. The phase of photoacoustic signal is measured as a function of modulated frequency using apparatus totally controlled by a computer system. The thermal diffusivity, effusivity as well as thickness of several buried layers are obtained independently through the best fit of experimental data according to the theoretical model. The multilayers of thin metal and alloy film are investigated. This method is proved to be valuable particularly in nondestructive examination of subsurface physical properties.展开更多
文摘The photoacoustic model of multilayer with a strong-absorbing surface layer is developed. The phase of photoacoustic signal is measured as a function of modulated frequency using apparatus totally controlled by a computer system. The thermal diffusivity, effusivity as well as thickness of several buried layers are obtained independently through the best fit of experimental data according to the theoretical model. The multilayers of thin metal and alloy film are investigated. This method is proved to be valuable particularly in nondestructive examination of subsurface physical properties.
