how to reharden aluminum after annealing it?

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Ok so here where I'm at all I seem to be able to get is 6063 t6 and of course I have to bend it sometimes so I anneal it, well I am on a project where I may need to reharden it, I've heard people say you can heat treat it to reharden it, if this is true how is it done?
Reply:sent to the Heat treater to get solution hardened and aged This is how we handle tubing that needs to be annealed before mandrel bending we send it out to be brought to a 0 state then send it back out to the desired state it needs to be in for serviceLast edited by WeldorWes; 02-12-2013 at 10:53 PM.Miller Xmt 350Lincoln Ln-25Ahp 200xSmith Gas Mixer AR/HTig is my Kung FuThrowing down dimes and weaving aboutInstagram http://instagram.com/[email protected]
Reply:Never even heard of a business like that, I use a torch to anneal it, after I do that I can bend it, of course I don't know if I can harden it back to t6
Reply:Solution heat treatment for 6063 involves heating the part to 970 +/- 10 deg F for a period of time, depending on maximum thickness, quenching ... usually in water ... then the part must be aged it at 350 deg. for 8 hours to regain T6 strength.  Another option is to warm bend your tubing.  At 350 degrees the elongation of 6063 T6 will be greater than fully annealed material, and will bend easily.  It will then return to full strength when it cools ...  if the time at temperature is short ... under 30 minutes.  Even if your process isn't perfect, I have used an O/A torch and Tempilstick, the resulting strength will be better than an annealed part.Dynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:If you don't need to reharden it fully, you can at least regain some of the hardness by just letting it sit and age (like, for example, a couple weeks.)  It should gain noticeably some hardness, compared to the "just annealed" state (which is very soft).  The longer you let it sit, the more it will harden (with diminishing effect).You may have heard of some aluminum heat treatment referred to as "artificial aging"?  Well this would be the "natural aging" approach.  May not be feasible if you need it to get hard in a hurry  ).If you want high as-welded strength without any waiting, consider using alloys that don't rely on heat treatment for high strength, like 5000 series.  (A common marine grade, nicely weldable also.)Edit: alternately, if you observe the required minimum bend radius for the material you're working with, you may be able to accomplish your bending while leaving the material in the heat-treated state (without bothering to anneal it in the first place).  Here are some guidelines on minimum bend radii for various aluminum products:http://www.aircraftspruce.com/catalo...minumalloy.pdfLast edited by jakeru; 02-13-2013 at 12:16 AM.
Reply:Thanks for the reply, origionally I tried bending the metal without doing anything to it, once I get around 10 degrees the metal cracks, I put the black sooty flame to it and the use a neutral flame to burn the soot off, I imagine this brings the metal to around 700 degrees, aneeled as I've been told, I let it air cool, then I bend it,  works great, I use schedule 40 pipe and tube when doing this, in this certain project its going to be holding some heavy lights that will be subject to salty air, I didn't know if there was a quick way to return the strength, I'm afraid quenching it may make it crack
Reply:Technically, annealed aluminum can not be age hardened, either naturally or artificially.  If the temperature of the material during "torch annealing" is hot enough to create a solid solution and cooled rapidly, then age hardening is possible.  A weld and part of the HAZ would certainly meet that criteria, but the temperature history of "torch annealed" material is an unknown and may not respond at all.Dynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A