looking for weldable, anodizeable castable metal alloys? 1

[GogiBOB]

Hi,
I am looking for castable metal alloy that can be welded as well as anodized.
Aluminum 712 seem to be good choices from what I've researched so far.
Is there any other choice of metal alloys?
I would appreciate any comment or thought!

Thanks,

 

[swall]

What strength level do you need?

 

[GogiBOB]

I need yield strength of at least 200MPa. The part I am designing will only experience compressive loads.

 

[swall]

Per the Aluminum Association Handbook, sand cast C355-T6 has a yield strength of 25,000 psi min, which is about 172 MPa. Sand cast 356-T7 has a yield strength of 29,000 psi min or right at 200 MPa. Both of these alloys are weldable (before heat treatment). Both are rated only 4 for anodize appearance (1 being best, 5 being poorest). Although your choice of 712 rates 2 for anodize appearence, it rates poorly in weldability at a 4. Yield strength for D712, condition F or T5 is shown as 25,000 min. You will need to compromise somewhere with your alloy selection.

 

[GogiBOB]

Thank you for the comments!
How about 5xx series? It seems like they are both weldable and anodizeable.
I am thinking about A520 since it is the strongest in the family with a yield strength of 180Mpa.
Would this be a good choice? I am having hard time finding mechanical properties of aluminum alloys.

 

[TVP]

I am not familiar with alloy A520. The standard North American grade for die cast Al with optimum anodizing appearance is 518.0 according to ASTM B85. Typical properties are YS = 190MPa, UTS = 310 MPa, El = 5%. Here are some good references on die casting alloys, properties, etc.:

Section 3 of NADCA Product Specification Standards for Die Castings / 2006

http://www.phbcorp.com/cms/uploads/downloads/Alloy Data-3.pdf

Primary aluminium casting alloys - Rheinfelden Alloys

http://www.rheinfelden-alloys.eu/c/..._l_id=11905&folderId=51634&name=DLFE-3204.pdf