Aluminium car chassi 2

[Moparigno]

Hello,
I'm starting the build of a race car chassi based on aluminium rectangular extrusions and stressed panels. All 8061 and 6082 aluminium, TIG welded.

I've read that a post heat process is recommended to increse the assembly stiffness. What is the correct procedure I should follow for heating and cooling the final welded chassis ?

thanks.

 

[swall]

I would suggest you pick up a copy of "Welding Aluminum: Theory and Practice" item SKU: WATP-23-516146 from the Aluminum Association.

http://www.aluminum.org

You can also find it at Amazon.

 

[TVP]

In addition to the reference that swall mentioned, I recommend reviewing the following links specific to welding aluminum:

http://www.alcotec.com/us/en/education/knowledge/techknowledge/index.cfm

http://www.alcotec.com/us/en/education/knowledge/qa/index.cfm

 

[BrianE22]

I'm not an expert an aluminum welding but I don't think the heat treat would affect the stiffness - just the strength.

 

[racookpe1978]

Be very careful about verifying all of the " little details" while "heat-treating" such an assembly.

Obviously, first - as noted above - decide on what time, temperature, heatup rates, cool-down rates, etc you want for the metal involved.

But in this case, you are trying to get uniform results over a very complex assembly of thin-walled and thick-walled extruded and welded members already put together into a hollow frame. So some parts (the corners, top and side pieces) are going to heat up rapidly since they are close to the furnace walls and higher up in the furnace. Others are going to be shielded from the wall of the furnace, be further from the heat source, be shielded from radiation by other members, be behind clamps or the jig you hold the frame in, etc.

The furnace gasses probably need to be moving to heat the surfaces and not allow stagnate or layered areas or be unduly influenced by distance to the radiating surfaces.

 

[WolfHR]

Even though it might require a bit more careful design and attention to detail, maybe it's worth considering the option of glued Al monocoque- Lotus Elise uses such chassis construction... And I guess it wouldn't need heat treatment afterwards.

 

[EdStainless]

The other approach is design and build in a few sub-sections. These are much easier to heat treat. Then assemble them either with glue or weld joints designed to be low stress and not needing heat treatment.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube