• Korean Journal of Materials Research
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• v.15 no.5
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• pp.306-312
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• 2005

The hydrogen sorption properties of $Ti_{0.3}Zr_{0.2}V_{0.5}$ NEC(non-evaporable getter) alloy and its hydrides were evaluated at room temperature. The alloy and hydride powders were prepared by the Hydride-DeHydride(HDH) method. The hydrogen sorption speed of $Ti_{0.3}Zr_{0.2}V_{0.5}$ alloy was measured to increase with the amounts of hydride phase in the getter. The hydrogen sorption speeds of $Ti_{0.3}Zr_{0.2}V_{0.5},\;(Ti_{0.3}Zr_{0.2}V_{0.5})H_{1.52},\;and\;(Ti_{0.3}Zr_{0.2}V_{0.5})H_{1.94}$ were 2.22, 3.14 and 5.08 liter/sec, respectively. The unexpected enhancement of hydrogen sorption speed with the presence of the hydride phase is considered to be due to the pre-saturation of hydrogen trap sites which can retard the diffusion of hydrogen in the alloy.

• Journal of Powder Materials
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• v.14 no.1 s.60
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• pp.50-55
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• 2007

The hydrogen sorption speeds of $Zr_{57}V_{36}Ti_7$ amorphous alloy and its crystallized alloys were evaluated at room temperature. $Zr_{57}V_{36}Ti_7$ amorphous alloy was prepared by ball milling. The hydrogen sorption rate of the partially crystallized alloy was higher than that of amorphous. The enhanced sorption rate of partially crystallized alloy was explained in terms of grain refinement that has been known to promote the diffusion into metallic bulk of the gases. The grain refinement could be obtained by crystallization of amorphous phase resulting in the observed increase in sorption property.

• Korean Journal of Materials Research
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• v.15 no.2
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• pp.79-84
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• 2005

The lowest activation temperature of a commercial vacuum getter reported so far in literature was about $400^{\circ}C$. Recently, $Ti_{0.3}Zr_{0.2}V_{0.5}$ alloy has been reported to exhibit the activation temperature lower than $200^{\circ}C$ when they are prepared as thin film. In this study, the alloy was prepared as bulk form and its activation temperature and hydrogen sorption properties were investigated in compliance with a standard method. The alloy powder was prepared by arc melting and subsequent HDH(Hydride-DeHydride) process. The activation temperature of the alloy was estimated from the ultimate pressure-temperature curve and located between $150^{\circ}C\;and\;200^{\circ}C$. The hydrogen sorption speed measured by an orifice method was 0.895 liter/sec which is comparable to thin film of same composition.

• Journal of Powder Materials
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• v.16 no.1
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• pp.28-32
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• 2009

The activation temperatures and hydrogen sorption rates of $Ti_{80-X}Zr_{20}V_X$ alloys were evaluated at room temperature. The alloy powders were prepared by arc melting and then hydride-dehydride(HDH) process. The alloy powders were apt to activate by increase of vanadium in Ti-Zr-V alloys. The easy activation was explained in terms of surface oxygen content which decreased with increase of vanadium on Ti-Zr-V alloys.

• Journal of the Korean Vacuum Society
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• v.14 no.1
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• pp.1-6
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• 2005

Getters are invariably covered with thin layers of oxides even in air. For the getter to function properly it is necessary to activate them by heating in vacuum during which the oxide layer is removed exposing clean surface. The so-called activation temperature is an important parameter along with gas sorption capacity since it determines the maximum temperature of a device in which a getter can be installed. Nevertheless, no standard method to measure activation temperature has been documented yet. In this study, a relatively simple method to measure the activation temperature based on the ultimate pressure measurement was suggested. The activation temperature of TiZrV alloy measured by the method was between 100℃～200℃.