Tantalum Alloys

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Tantalum Alloys
Ta has the same crystal structure and identical
atomic size as Nb and the two metals have very
similar chemical and mechanical properties Ta is
prepared by electron beam melting and powder
metallurgy and then formed by cold working
processes (similar to Nb alloys) It is unique as
a bcc transition metal because it can be cold
formed at temperatures down to -200 oC
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Tantalum Alloys
Ta electron beam melted cold rolled 82 -
annealed for 45 minutes at 2100 oC
Recrystallized bands were caused by variation of
cold work due to coarse grains
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Tantalum Alloys
Pure Ta has excellent resistance to reaction from
body fluids and tissue and is thus used for
dental and hip prostheses Ta alloys containing
2.5-10 W and 30 Nb 5 V have been
proposed. There is no strong motivation for
their development as high temperature materials
because due to their lower strength-to-weight
ratio they are less favourable to Nb alloys for
service at temperatures below 1375 oC and less
favourable than Mo alloys at temperatures above
1375 oC
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Tantalum Alloys
However, because pure Ta is one of the most
corrosion resistant materials, it is now being
deposited as Ta gas onto material surfaces that
require extra-strong protection to form a thin,
protective film of Ta. The attached article
explains the deposition method at high
temperatures and gives some applications such as
the production of H, biomass to ethanol, oil
gas, etc that involve a highly corrosive
environment .
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