Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!att!cbnews!military
From: raymond%carme@uunet.UU.NET (Raymond Man)
Newsgroups: sci.military
Subject: Aluminum Ships
Message-ID: <1990Jun29.025702.7274@cbnews.att.com>
Date: 29 Jun 90 02:57:02 GMT
Sender: military@cbnews.att.com (William B. Thacker)
Organization: AME Dept., Univ. of Arizona at Tucson
Lines: 35
Approved: military@att.att.com



From: raymond%carme@uunet.UU.NET (Raymond Man)

In <1990Jun28.025954.19601@cbnews.att.com> George William Herbert maintained 
that
>Aluminum in ship structures does not burn in shipboard fires.

We need to talk to chemists here. I believe (from what remain of my
high school chemistry) that Al reaction with O is exothemric. So
given a high enough initial temp., the reaction will sustain itself,
in other words, burn. For steel, I believe it is endothermic, so
it will not burn. There is no reason to suppose shipboard fires
burn cooler than any fire and I imagine the materials on a warship
give much hotter flame than usual.

[mod.note:  Will a metallurgist do ?  8-)  Yes, the oxidation of aluminum
is exothermic, very much so.  The thing is, Al2O3 (blasted ASCII...) forms
a very stable, thin film over the aluminum, which greatly inhibits further
oxidation, even when the aluminum is molten.  Hence, aluminum can be (and 
routinely is) melted and cast in open air.  So long as it doesn't become
finely divided, it's quite resistant to uncontrolled oxidation (fire,
y'all 8-)

This is not true for the more reactive titanium and zirconium families.
Thermite (a mixture of powdered aluminum and iron oxide, which generates
great heat in the exchange reaction forming iron and aluminum oxide)
works because of the fine division of the components.   The process is
known as "aluminothermic reduction," for vocabulary buffs.  - Bill ]

The rest of Mr. Herbert article I tend to agree.
Disclaimer: Nothing more than explicitly stated is intended to be conveyed.
Just call me `Man'. 
"And why take ye thought for "    --   Matt. 6:28
raymond@jupiter.ame.arizona.edu