Inert Gas Analysis Research Articles

Deoxidation purification of La–Ce alloy by solid state external gettering

Deep removal of interstitial impurities such as oxygen from La–Ce alloy is challenging due to their strong affinity and high chemical reactivity with oxygen. The method of external getter was employed to investigate the deoxidation process and thus to explore the deoxidation mechanism.Quantification of relevant elements including Ca, Y, and O were analyzed by inductively coupled plasma-mass spectrometry(ICP-MS) and inert gas analysis (IGA). The analysis results show that oxygen concentration decreased from 550 ppm to 54 ppm and 55 ppm respectively in La–Ce alloy by Ca and Y as the external getters. The interaction between the getters and base metal, the chemical driving force and deoxidation mechanism were discussed in details.

Behavior of impurity elements in pure gadolinium during ultra-high purification

Deep purification, especially the removal of trace elements from the rare earth metal gadolinium (Gd) is challenging, due to their strong affinity and high chemical reactivity. Herein we present an effective approach to explore the purification mechanism via a novel Gas-solid two-phase method under high vacuum. All impurity elements were analyzed by glow discharge mass spectrometry (GDMS) and inert gas analysis (IGA). Both metallic impurities and oxygen can be reduced effectively after the purification process, especially the oxygen (O) concentration is close to zero. The chemical driving force, migration paths, migration laws and mechanisms of various impurity elements were studied in detail. Interactions of impurity elements during ultra-high purification process had been explored by using the specific technology of secondary ion mass spectroscopy (SIMS).

Research on the removal of impurity elements during ultra-high purification process of terbium

Ultra-high purification of terbium (Tb) by vacuum distillation and external getter was investigated. More than 20 kinds of impurity elements were analyzed by glow discharge mass spectrometry (GDMS) and inert gas analysis (IGA). The analysis results show that total impurities decrease from 1114 ppm to 63 ppm. High volatile metallic impurities such as Mg, Ca, Mn, Zn, and Tm can be reduced effectively after distillation. The oxygen (O) concentration can be decreased to 1.8 ppm after deoxidation process, which currently is one of the best results in the contemporary studies. The chemical driving force for deoxidation has been calculated in this paper. The different deoxidation results of Tb metal with various purity have been discussed in detail using the secondary ion mass spectroscopy (SIMS). Finally, a ultra-high purity Tb with low concentration of O can be obtained through vacuum distillation and external getter method.