Hi all,
Lockheed had trouble with titanium parts for the SR-71 becoming contaminated
by chlorinated water being used to rinse parts. The chlorine gets into the
metallic crystal lattice and causes stress fractures when exposed to thermal
cycling.
Jim in Palmdale
----- Original Message -----
From: Higginbotham Land Speed Racing <saltrat@pro-blend.com>
To: <land-speed@autox.team.net>
Sent: Wednesday, February 16, 2000 6:16 PM
Subject: Fwd: Re: Titanium-Brake clean
> >Date: Wed, 16 Feb 2000 18:15:15 -0800
> >To: Dick J <lsr_man@yahoo.com>
> >From: Higginbotham Land Speed Racing <saltrat@pro-blend.com>
> >Subject: Re: Titanium-Brake clean
> >
> >Close! Here's another one!
> >Chlorinated solvent and water makes hydrochloric acid under the right
> >temperature conditions. Not good for anything that is corrosion
susceptible.
> >Especially aircraft hydraulic systems. Which sometimes have Titanium in
them.
> >Skip Higginbotham ( 80 today)
> >
> >At 11:21 AM 2/16/00 , you wrote:
> >>
> >>
> >>--- DOUG ODOM <popms@thegrid.net> wrote:
> >>> List, I just came across this.
> >>> "Do not use chlorinated solvents such as
> >>> "Brake Parts Cleaner" around
> >>> or on any titanium components (valves,
> >>> retainers, etc.)"
> >>> Does anybody know the reason for this or what
> >>> is the problem.
> >>
> >>
> >>I'll take a SWAG (scientific wild ass guess) at
> >>this. The titaniaum brake systems are composed
> >>of several pieces, some of which will probably be
> >>more common steel. The chlorinated liquid
> >>solvent could react between the steel parts,
> >>which act as a cathode, and the titanium part,
> >>which act as an anode, and you end up with a
> >>primitive chemical battery. The solvent changes
> >>it's chemical characteristics from straight
> >>chlorine to any number or chorides (salts) and at
> >>the same time changes the chemical composition of
> >>the steel and titanium, probably making them more
> >>brittle, if not actualy disolving them after long
> >>periods of time. Not good for brakes. How
> >>'bout one of you rocket scientists grading my
> >>paper and if it's right, I want to print it and
> >>take it home to my high school daughter! hee hee hee.
> >>
> >>=====
> >>.............................
> >>..........Dick J.............
> >>......(In East Texas)........
> >>....FX/GMR SC/P250-2........
> >>.....Shelby 427 Cobra.......
> >>.Hemis and Flatheads Forever.
> >>.............................
> >>Do You Yahoo!?
>
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