Measuring the Expansivity of Tungsten at Elevated Temperatures using laser of wavelength 532 nm

Abstract

In this wok, we perform a simple experiment to measure the linear expansion of a tungsten wire over the temperature range 300-3600 K. This experiment is based on the using of a laser with a wavelength of 532 nm to light the ordinary tungsten filament of P21W car lamps under gradual heating, which leads to a change in the dimensions of the filament, the dimensional changes are measured in the shadow images, these changes are associated with current-voltage values in order to calculate the coefficient of linear thermal expansion CTE(The coefficient of thermal expansion) in this field. In addition to measuring the frequency of vibration of the wire in the  field 300-1400K. This low-cost experiment with tungsten enables science students to understand the thermal behavior of tungsten as a refractory metal, and allows for many low-cost measurement to aid in future refractoriness and to test new calasses of refractory materials.