Short lesson on aluminum

[Frank ZX]

I'm a aircraft mechanic at a major airline.I finished a 2 week class on sheet metal a few weeks ago.I thought I would share a few thing about aluminum I have learned.First off,aluminum comes from dirt.There are different types of aluminum,7073,2024,etc.Most aluminum is mixed with zinc,copper,and sometimes other exotic metals.There are also many different heat treat processes T3,T4,t6,etc,which gives it strength.
Some people think aluminum will not rust like steel,BUT it will corrode if not maintained properly.Corrosion will spread just like rust,and eat a hole in aluminum.Some times in the manufacturing process there are contaminates in the metal and it will corrode from the inside out.When this happens the aluminum will grow to several times it size,and turn a white chalky color.
So to keep your aluminum boat looking and performing like it should,Keep it clean.
If you see a white chalky spot on your boat,sand it out with a ScotchBrite pad,and acetone.And don't concentrate your sanding pressure just on the spot of corrosion,blend it out a few inches away from the spot of corrosion.

 

[Jim]

Thanks for the info! Good to know!

 

[Waterwings]

Good info ! Thanks 8)

 

[FishingBuds]

ah HA! so thats what that stuff is :?

Thanks for the info =D>

 

[bassboy1]

Yes, it does corrode, but not as quickly or as readily as steel, which makes it nice for boats.....

And actually, some corrosion is good for aluminum. If you have ever cut a piece of aluminum stock, and the outside seemed dull, you would notice that the inside was shiny. After a while, the cut piece would dull again. That is a form of corrosion that happens upon contact with air. This corrosion protects the rest of the aluminum. To make shiny aluminum boats, they have to clear cut it soon after being made. And, if you brush a rock, you see that the scratch will soon dull over. This is that corrosion taking effect.

Not many people know this, but aluminum actually will rust. It won't happen with contact with water, but with liquid mercury.

I assume your class went over the properties of each alloy. Which alloy bends better, which is stiffer, which has the best corrosion resistance, the stiffest, etc. I am still learning the advantage to each alloy myself. If you could post that, I can see this post as being a real useful thread and possibly worthy of the front page, if Jim likes it.

 

[Captain Ahab]

Nice info thanks

 

[BLK fisher]

Good to know. Thanks for the report.

 

[seif5034]

thanks for sharing. More useful information that makes this site great!!!