| First any tempers are lost and overaging may occur in some alloys where the metal is further weakened. The only way to avoid this is to change alloys. Stainless steels will also have similar problems which can only be avoided by keeping out of the temperature range of about 800F-1600F. Once chromium carbide precipitates in this temperature range, the grain boundaries will rust which can lead to these failures. To avoid this try 316, 347, or even 304L alloys. And turtleboy is right, they wouldn't rust if oxygen were kept out. Find a way to do this any you'll be a rich man. A good approach may be to used molybdenum disulfide or boron nitride lubricants on the threads during assembly. If they dont fully oxidize in service, they will ease the removal of the hardware later.
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