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Structural alloy for bright dipping

My question is kind of a 2-parter in that most answers tend to only give insight in to only one side of the equation. Currently I have a fledgling company machining automotive suspension components out of 6061-T6 billet. Initially I chose 6061 for it's overall strength properties and economical cost. it's simply the do-all alloy. ideally I'd like to improve the quality of my bright dip anodizing to match my competitors finishes. All investigation in to bright dipping seems to return that the 6000 series variants of 6063 and 6043 as best suited for bright dipping. however, these are commonly referenced as extrusions for architectural use while being contra-indicated in terms of strength relative to 6061. Now this contra-indication is a deal breaker regarding fatigue issues surrounding my intended application. Now I've heard there might be a better load bearing variant of 6063 called 6063A that might be a solution and I know 7000 series alloys offer even greater strength relative to 6061. Ideally I would like to use 7075, but I've even seen information both pro and con regarding 7000 series alloy compatibility for bright dip...? so, what alloy is most compatible for bright dipping that's offered as machineable billet and strikes a balance between strength and cost...? 7016 and 7029 are the formulations I've heard in the 7000 series, but I'm not thinking they are anywhere near being as cost effective as the more common 7075 or 6061.

Roman S. Tarnacki
aftermarket performance - Richmond, Virginia
2006