perchlorethylene and perchloric acid and aluminum corrosion

[russf]

Does anyone know if perchlorethylene or perchloric acid are corrosive to aluminum alloys 3003, 5083 or 6061-T6? Information such as temperature, concentration and other interactions would be helpful.

 

[tedg]

In the pure state (ie in theory) the solvents do not attack aluminum or the said alloys. However, in practice they often do, especially with parts of high specific surface and in the presence of cutting, grinding or boring chips. These surfaces appear to catalyse a breakdown of the solvent and production of chloride ion (often HCl) which strongly attacks aluminum. Elevated temperature hastens the process, but in our experience, high specific surface is the prime initiator. Once the chloride attack starts, reaction becomes exothermic and can quickly lead to a fire and explosion hazard. Take care.