Welding Tantalum for High Temperature Applications

Abstract

A device is described which can be used to weld tungsten, tantalum, and molybdenum. The general problem of fabricating tantalum process equipment from tantalum sheet is discussed.

Effect of solutes from the sixth period of the periodic table on the melting point and the allotropic transformation temperature of praseodymium

“…Two methods of checking for this were used. In the arc-welding of Ta (21), a volatilizing component can be seen as a different color in the Ta tip to Ta crucible arc.…”

“…All of the alloys were contained in Ta crucibles be cause Ta does not react with Pr (20) and Ta crucibles are easily fabricated (21). Dennison and co-workers (20) showed the solubility of Ta in Pr, at the melting point of Pr was 0.0055 at.% Ta.…”

“…Alloys were prepared by cutting off the lid of the above crucibles, weighing the amount of solute added to within + 0.1 mg, using an Ainsworth electronic balance. A new Ta lid was welded on the crucible in an arc-welder under a partial atmosphere of helium (21). Fortunately, the density of the elements from period six is greater than that of Pr, except for Cs and Ba, and so it was assumed alloying occurred as the solute settled down through the molten Pr.…”

The effect of solutes from the sixth period of the periodic table on the melting point and the allotropic transformation temperature of praseodymium

“…All of the alloys were contained in Ta crucibles be cause Ta does not react with Pr (20) and Ta crucibles are easily fabricated (21). showed the solubility of Ta in Pr, at the melting point of Pr was 0.0055 at.% Ta.…”

“…showed the solubility of Ta in Pr, at the melting point of Pr was 0.0055 at.% Ta. (21). Fortunately, the density of the elements from period six is greater than that of Pr, except for Cs and Ba, and so it was assumed alloying occurred as the solute settled down through the molten Pr.…”