There are many different alloys of aluminium designed with different characteristics like the ability to be turned, welded or non corrosive.
Different elements are added to the alloy to increase strength as well.
The other thing that increases strength in some aluminium alloys is heat tempering.
If you have ever purchased ali you may have noticed that it has a series like 6061 and at the end there may be T6.
The 6061 tells what elements are in the alloy while the T6 describes the temper.
To reduce the strength of a T6 ali alloy all you have to do is anneal it with heat.
This will make it much more easier to work with a hammer.
Tight nuts
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