Aluminum Alloys 3105 and 3004

My two cents is rather broad, but hopefully applicable. Switching from a 3xxx series to a 5xxx series can have an adverse affect on the rate of corrosion seen, since 5xxx is for high corrosive environments; of course if the cost savings benefit offsets this potential, it becomes a "no brainer".

I don't know about the 3xxxx series aluminum. I recommend getting some and making a sample from it for testing.

We use 5052 in 10 gauge and 12 gauge sheets. It will form just fine with breaking. We have no problems welding either.

We also use 6061 aluminum for parts that are machined because it doesn't warp and is in easy on tooling. You can use 2017A for the same purpose however in the USA it comes primarily in round bar form only. Europe is big on using 2017A in other forms.

Yeah I've used 5052 extensively over the years. It's good stuff. So far, my research seems to suggest that the 3004 that is being recommended as a replacement is inferior in most ways that are relevant to our applications. i.e. lower shear, lower ultimate, lower yield, lower ME .... and even heavier. And of course, corrosion. So that's probably a no-go.

The 3105, on the other hand, that we're considering to replace 3003, does appear to be "stronger", with other preferable qualities over the 3003 that we now use. But these things are all based on spec sheets and the like. I was hoping there were other people that have considered these less well-known alloys as cost savings measures, and have had some real world experience with them. That's always best. As a rule you get what you pay for, but occasionally there are exceptions. That's why I'm exploring these things.

These are all sheet applications. So there is no machining involved, nor even structural shapes. So the 6000's don't apply, which is what I use in those structural and machining type situations.