Thesis - Oztek_Muzaffer_T_200508_MA

Table 1: Effects of various milling parameters on hydrogen capacity.
Mill type
Milling variables Fritsch Pulverisette Spex8000
Milling vial SS a SS SS WC b WC WC SS
Atmosphere Ar Ar H 2 Ar Ar Ar Ar
Speed, rpm 100 300 300 1725 1725 1725 1725
BPR 10:1 10:1 10:1 10:1 1:1 1:1 1.7:1
Milling time, min 10 10 10 10 10 30 30
% H None 0.60 0.56 1.06 0.54 0.66 0.76
a Stainless steel
Tungsten carbide
3.1.3.5. Dehydriding of LaNi 5
The thermogram representing the dehydriding of LaNi 5 is shown in Figure 21. Of
the two endotherms; one was observed during the delay of heat transfer to the sample,
and the other after heating started. This indicated that some hydrogen was released at
room temperature (Figure 22), and then after heating starts the rest was given off.
Dehydriding was complete when the sample temperature reaches about 340 K.
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