Evaluation of Thermal Conductivity from Relaxation of Laser-Induced Incandescence of Carbon Thin Superficial Layers
The effect of thermal conductivity on pulsed thermal emission, known as laser-induced incandescence (LII), of thin superficial layers of carbon samples with rough and polished surfaces was studied. LII was excited by irradiation of the carbon surfaces with nanosecond pulses of a YAG:Nd laser (1064 nm) with intensity of 3-40 MW/cm2. The results of the oscilloscope measurements of the LII pulse shape and calculation data demonstrated a significant reduction in the duration (FWHM) of the thermal emission pulse and its prolonged decay. The observed phenomenon was attributed to an increase in the thermal conductivity of the superficial layers of carbon samples.