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The corrosion of aluminium is generally recognized to be a major problem. What new technologies or technics might be used in aluminium wiring to get away from the corrosion issue?.

huytergan
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    No. I don't see any solution explained over there in regard to corrosion issue. Do you? – huytergan Jun 26 '19 at 11:46
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    ”Generally recognized"? It's an old wives' tale/urban myth/moral panic. In other news, flying is a scary/dangerous way to travel. – Harper - Reinstate Monica Jun 26 '19 at 12:02
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    @Harper Corrosion is a real problem if it's not properly solved. – huytergan Jun 26 '19 at 12:10
  • "Do you think it might have been used [...]?" clearly asks for an opinion-based answer. Moreover, although the title is quite clear, the description is confusing and broad as it asks several questions. – Manu H Jun 26 '19 at 12:13
  • What corrosion issue? What are you referring to? – CrossRoads Jun 26 '19 at 12:14
  • @CrossRoads galvanic corrosion is the most common cause of corrosion for Aluminium – huytergan Jun 26 '19 at 12:16
  • @ManuH I don't see anything wrong by asking and learning your opinion and scientific knowledge. – huytergan Jun 26 '19 at 12:18
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    Yes. But I've not seen any stories reported on galvanic corrosion being an issue for Airbus. So what are you referring to? – CrossRoads Jun 26 '19 at 12:19
  • You made me smile, cause I'm already asking what made Airbus have not an issue of galvanic corrosion. Corrosion issue is something that exists in stage of building an aircraft. If airbus flies, which's true,they did something not have the corrosion issue. – huytergan Jun 26 '19 at 12:20
  • The A380 has not had any such wiring corrosion issues. Aluminium inside the insulation will not corrode because it is not exposed to ambient conditions. Copper corrodes too, but not inside insulation. Tons of planes are made of aluminium. The metal is treated to prevent corrosion. This is a non-issue, and it's perfectly safe, as answered in the question of which this is a dup. – Juan Jimenez Jun 26 '19 at 12:22
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    My plane uses a big AL wire from the battery in the tail up to everything else in front of the pilot,and then copper everywhere else. Big connector, crimped onto the wire and treated with something (I don't recall what anymore), it has lasted for 45+ years. – CrossRoads Jun 26 '19 at 12:22
  • @huytergan as exlained in the help center, this is not a discussion forum but a Q&A website. – Manu H Jun 26 '19 at 12:23
  • @ManuH okay, I'll fix it up – huytergan Jun 26 '19 at 12:24
  • @CrossRoads and it's not even AA-8000 alloy (not invented yet) which is now a Code requirement in aluminum house wiring. – Harper - Reinstate Monica Jun 26 '19 at 13:08
  • Your title and the body of your question ask two completely different questions. The one in the title seems eminently answerable; the one in the body is asking people to speculate about the future. – David Richerby Jun 26 '19 at 13:51
  • I have to agree with David. If you want to ask two questions, please do, as separate questions, not two in the same one. – Federico Jun 26 '19 at 15:52

1 Answers1

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The mechanisms by which aluminum corrodes are well-know and the measures needed to prevent it are similarly known to design engineers.

Aluminum corrosion via direct attack is an issue where the aluminum is exposed to air and the air contains moisture, and is made worse when salts are present in the environment and at certain pH ranges. It is prevented by encapsulating the aluminum in either an impervious coat of paint or plastic or a coating of intentionally-grown aluminum oxide. In an airplane, the insulation on the wire will prevent corrosion by direct attack.

Aluminum corrosion by galvanic action occurs when the aluminum is bonded directly to or in contact with a piece of metal that has a different position in the galvanic series, and the joint is wet or at least moist with water. You prevent it by excluding water from the joint by sealing the joint with glue or enclosing it in a housing that is airtight, and by coating the joint with a grease or oil that excludes water. In an airplane's wiring system, this would be done with a plastic plug-and-receptacle for the joint that keeps water out.

Electrical fires in wiring system connectors that contain aluminum wire joined with copper wire occur when the physical joint between them is vibrated or worked back and forth, which scrapes the native oxide off the aluminum in the joint, promoting more oxide growth which is scraped off, etc. which eventually leads to loading the joint with aluminum oxide and creating high contact resistance between the aluminum and the copper wire at the joint. I-squared-R heating at the degraded joint then sets the insulation on fire. This can also happen by temperature-cycling the joint which will cause the joint surfaces to be worked back and forth and once the joint begins to show resistance, then the heating occurs right inside the joint and the process accelerates itself.

In airplanes, houses, and cars where aluminum and copper wire must be joined, a special connector is used where the metals meet in which the crimp joint is exceptionally tight and the joint is loaded with a grease or chemical paste containing inhibitors that halt the oxidation of the aluminum.

niels nielsen
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