The thermal properties of high purity and fully dense tungsten produced by chemical vapor deposition

Highlights: • High purity and fully dense CVD-W samples were prepared. • The deposition rate of CVD-W is higher than 0.6 mm/h. • Thermal conductivity of CVD-W is higher than that of forged-W. • CVD-W had a higher threshold energy of crack initiation than that of forged W. • CVD-W has higher energy absorption than that of forged-W. - Abstract: The ultra-high purity (>99.9999 wt.%) and fully dense (19.23 g/cm³) tungsten (W) by chemical vapor deposition (CVD) was prepared with the deposition rate higher than 0.6 mm/h. The thermal diffusivity, specific heat, heat conductivity and coefficient of thermal expansion of CVD-W at the temperature range of 473–1273 K were measured. Thermal shock tests were carried out on a 60 kW electron-beam material testing scenario to investigate the crack-resistant performance of CVD-W, and the crack initiation threshold energies of CVD-W were achieved in 5 ms heating duration. Compared to forged-W, the higher heat conductivity (160.5–111 W/(m K)) and threshold energy of crack initiation (1.1–1.65 MJ/m²) of CVD-W can be attributed to the material characteristics including high purity, fully dense, rough surface composed of pyramid-like grains, and the columnar grain structures