Measurement of Temperature and Emission of Laser-Heated Lead Samples during Heating and Cooling

摘要

Surface temperatures resulting from exposure of lead samples to a continuous wave laser beam were measured. The experiment used six sizes of square samples (2.5 to 10 cm on a side), all cut from sheets of 0.17-cm thickness. The CW-CO2 laser produced 45 watts maximum output power at 10.6-micrometers wavelength, and illuminated a spot size of about 0.4 sq cm on the samples. Iron/constantan thermocouples were attached at five or six locations on a sample and monitored temperatures during the heating and cooling period. The experimental results plotted as temperature versus time at various monitor points indicated that the cooling process is more rapid than the heating process. Data plotted as temperature profiles across the sample surface at various instants of time indicated that 1) the difference in temperature between the front and back of the sample was very slight, and 2) the center of the sample heated and cooled more rapidly than the sample edges. (Author)