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Baking 6063 aluminum to Rockwell 70

Hello everybody,

I am Chris from the Netherlands and I work for a wholesale company in outdoor furniture. Is there anybody who can give an answer to my following question: Is it possible to have an aluminum tube frame (to make a chair) made of alloy 6063 with a hardness of 4 Webster (approx. 40-45 Rockwell E), to have it 12 webster (approx. 70 rockwell) after 5 hours in a furnace of 200 °C? If not, what should be the maximum hardness after 5 hours in the oven?

Chris Montijn
designer - Breda, Brabant, Netherlands
2004

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You're not saying what real-world thing you are trying to accomplish, or why, Chris, and that makes answering your inquiry difficult. My first question is: if you are trying to improve the hardness, why aren't you hard anodizing it instead? If you are trying to improve the strength, why aren't you buying stronger tubing? And if you want to know whether baking for 5 hours at 200 °C will change the hardness To Rockwell 70, why aren't you just putting a scrap in the oven for 5 hours and checking the hardness? Sorry, I would like to try to help, but I can't figure out what is in your head.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

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I used to "age" a lot of 6061 and 6063 alloy when I worked at an extrusion mill (about 16 years ago), but I'm a little fuzzy now on which alloy got what process. If your supplier sent you a bunch of soft product, send it back and tell them to do it right! Otherwise I believe you have the right formula, although your temp might be a little bit high. You should get a 12-14 range in about 4 hours, try one and find out.

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
2004