As mentioned Drrsutliff, the surface of aluminum oxidizes to create a coating of aluminum oxide. This surface adheres strongly to the aluminum and protects the unoxidized aluminum beneath it. Steel, as we know also oxidizes, however this creates rust which progressively falls away from the metal beneath thus allowing the oxidation to spread.
If aluminum comes into contact with salts or caustics it will cause the oxidizes to go on and spread like rust on steel.
Anodization of aluminum thickens the hard oxide layer and increases the protection against corrosion. This is generally sufficient for most applications.
I live in Quebec. We are not close to the sea but during winter the cities spread copious amounts of salt on our roads. IME The salt seems to have little impact on aluminum wheels. Mind you, I remove my al wheels and replace them with old rusty steel rims. Many other car parts are also made of al such as engine blocks and heat exchangers. I have never heard of them failing due to corrosion.
All this to say, that for audio applications I would not be the least bit worried with use of aluminum. The question is are there other materials, for audio applications, that will perform better such as carbon fibre or Kevlar?
Formerly, I worked for a leading aluminum producer.
As for toxicity, aluminum is not toxic and eating from it is in no way dangerous. Good luck not eating food that is or was in contact with al. Think al foil.
As for the link with Alzheimer's, my understanding is that al is found in the brains of patients but that arrives their "naturally" and is not a result of exposure.
If aluminum comes into contact with salts or caustics it will cause the oxidizes to go on and spread like rust on steel.
Anodization of aluminum thickens the hard oxide layer and increases the protection against corrosion. This is generally sufficient for most applications.
I live in Quebec. We are not close to the sea but during winter the cities spread copious amounts of salt on our roads. IME The salt seems to have little impact on aluminum wheels. Mind you, I remove my al wheels and replace them with old rusty steel rims. Many other car parts are also made of al such as engine blocks and heat exchangers. I have never heard of them failing due to corrosion.
All this to say, that for audio applications I would not be the least bit worried with use of aluminum. The question is are there other materials, for audio applications, that will perform better such as carbon fibre or Kevlar?
Formerly, I worked for a leading aluminum producer.
As for toxicity, aluminum is not toxic and eating from it is in no way dangerous. Good luck not eating food that is or was in contact with al. Think al foil.
As for the link with Alzheimer's, my understanding is that al is found in the brains of patients but that arrives their "naturally" and is not a result of exposure.