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According to corrosion manuals, mercury causes corrosion of aluminum at 25°C. The mechanism of corrosion is as follows: mercury does not react with aluminum, but aluminum does dissolve in mercury to form an amalgam. A small portion of the aluminum that dissolves in mercury reacts with oxygen to form aluminum oxide; aluminum oxide does not dissolve in mercury and floats to the surface. This allows more aluminum to dissolve in mercury, and any aluminum that dissolves in mercury will react with oxygen to form aluminum oxide. This process repeats itself, with the amount of mercury remaining unchanged while all the aluminum is oxidized. Under normal conditions, the aluminum surface is covered with a dense layer of aluminum oxide, which prevents air from coming into contact with the aluminum and thus protects it, preventing corrosion. Example: Mercury causes metal embrittlement, leading to through-wall cracking at the butt welds of 5083-0 aluminum alloy pipes in an ethylene plant. Based on this finding, ultrasonic testing was conducted on 226 of the more than 400 butt welds in the pipes to detect cracks. Another weld that has deteriorated due to mercury was found. Recruit a welding team with experience in dealing with mercury pitting to repair the welds. The correct measures are: installing a sulfur-impregnated carbon mercury removal bed, and replacing the aluminum equipment before installing the mercury removal bed. Failure mode description: Key variables, common locations. Liquid metal embrittlement – Catastrophic brittleness occurs when normally ductile metals come into contact with liquid metal and are subjected to tensile stress. Such as the combination of stainless steel and zinc, and copper alloys and mercury. Local metal structure, tensile stress, liquid metal encountered. Mercury in crude oil becomes concentrated and focused at lower points in certain equipment (such as the pipes of condensers) during the distillation process, leading to the failure of process equipment due to the intrusion of mercury into the refining system.