Several instances have been reported of violent reactions of titanium and liquid oxygen which appeared to be related to impact.
The impact sensitivity of titanium in LOX has been investigated rather extensively. It appears that the ignition of titanium under impact occurs in the following sequence:
(1) The impact exposes fresh metal and results in some gaseous oxygen being formed at the point of impact.
(2) The gaseous oxygen reacts with the fresh metal in an exothermic reaction.
(3) The heat generated raises the metal temperature sufficiently to result in localized dissoluton of any TiO2 film that might form.
(4) Thus a protective oxide film does not build up and the reaction proceeds rapidly between the base metal and oxygen.
Ignition of massive titanium is observed in gaseous oxygen at liquid-oxygen temperatures at pressures of about 100 psi and above.
This critical pressure limit is lowered only slightly as the temperature of the oxygen is raised to ambient temperature.
[+] [-] knd775|6 years ago|reply
It seems that no one really knew that titanium could ignite.
edit: Maybe not. Looks like this was a known failure mode for titanium https://apps.dtic.mil/dtic/tr/fulltext/u2/613553.pdf
[+] [-] magicalhippo|6 years ago|reply
The gist of it, as I could see:
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Several instances have been reported of violent reactions of titanium and liquid oxygen which appeared to be related to impact. The impact sensitivity of titanium in LOX has been investigated rather extensively. It appears that the ignition of titanium under impact occurs in the following sequence:
(1) The impact exposes fresh metal and results in some gaseous oxygen being formed at the point of impact.
(2) The gaseous oxygen reacts with the fresh metal in an exothermic reaction.
(3) The heat generated raises the metal temperature sufficiently to result in localized dissoluton of any TiO2 film that might form.
(4) Thus a protective oxide film does not build up and the reaction proceeds rapidly between the base metal and oxygen.
Ignition of massive titanium is observed in gaseous oxygen at liquid-oxygen temperatures at pressures of about 100 psi and above. This critical pressure limit is lowered only slightly as the temperature of the oxygen is raised to ambient temperature.
[+] [-] Gibbon1|6 years ago|reply