| Abstract: | Summary A study was made of the welding of iodide zirconium spheres of 2-ram diameter in a purified helium atmosphere (3 atm gauge) and in a vacuum (10–4–10–5 mm Hg). It is shown that welding in helium (1265–1810°C occurs mainly as a result of diffusion material transport, whereas welding in a vacuum (1500–1800°C is controlled primarily by an evaporation-condensation mechanism. The data obtained are used to evaluate the self-diffusion and evaporation parameters and to derive equations expressing the self-diffusion coefficient and vapor pressure of zirconium as functions of temperature over the range investigated.Translated from Poroshkovaya Metallurgiya, No. 6(66), pp. 41–46, June, 1968.The authors are indebted to V. V. Khromonozhkin for helpful discussion and to V. G. Osintsev for making available the test materials. |
