Thermal analysis gaseous helium

Markova et al. (1967) investigated the terbium-yttrium system by means of microscopy, X-ray diffraction, thermal analysis, hardness and electrical resistance measurements. Their starting materials were distilled yttrium of 99.6 to 99.7 (wt )% purity and terbium of 98.5 to 99% purity. Impurities in their terbium included yttrium, gadolinium, dysprosium, calcium, copper, iron and tantalum. Both metals contained gaseous impurities. Alloys were melted in an arc furnace under a helium atmosphere and annealed at 850°C for 70hr. 

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