Thread: County 4bd1 aluminum radiator

Welded aluminium has serious fatigue issues unless you can get it fully heat-treated afterwards or keep the stress levels right down. The heat-treatment isn't a practical option, they are probably welding cores and tanks of different alloys together anyway. The stress will come from thermal effects and body twisting.

Notice that factory aluminium radiators aren't welded.

Dougal, how do you heat treat 1000 series ?

Surely rad cores aren't anything trick ?


The biggest issue with aluminium cores IMO is stray current.
You can lose a core in a matter of weeks from one crook earth, not that a Landy would ever suffer from a poor electrical connection

Originally Posted by rick130

Dougal, how do you heat treat 1000 series ?

Surely rad cores aren't anything trick ?


The biggest issue with aluminium cores IMO is stray current.
You can lose a core in a matter of weeks from one crook earth, not that a Landy would ever suffer from a poor electrical connection

1000 series aluminiums are showing up on matweb as H treated, which is mechanical cold worked. Depending on the sections you've got you can get a harder fractured grain in the un-touched aluminium which will transition to a softer and coarser grain in the weld heat affected zone (HAZ). So if it's going to break, it'll do it right at the edge of the HAZ.

You would be limited to annealing the whole radiator to soften it all up and destress the welded areas.

I don't know what grade the radiator builders use though.

Originally Posted by rick130

...

Dougal, how do you heat treat 1000 series ?

Surely rad cores aren't anything trick ?

...

...This 6061-T6 Aluminum Radiator...

AWR builds high performance aluminum radiators for race cars, with extreme cooling needs

All PWR radiators are manufactured by hand from our State of art facilities on the Gold Coast. PWR produce all product from Hi-grade Aluminium

http://www.horsepowerinabox.com/HPIAB2/category79_1.htm

This radiator using aluminium alloy 6061.

http://www.redlinegti.com/forum/view...&view=previous


Btw 1000 series is too soft to be a serious option. I once had a 1" thick by 4" (cross section) piece of 1000 series. You could bend it by hand.

6061 has plenty of strength after a T6 heat-treatment (solution heat, quench, artificial aged), but touch it with a welder and it turns to that same as cast soft stuff Ben just mentioned.

People suffer endless pain trying to repair 6061 bike frames with heat-treating them. Weld, ride, crack. Repeat until you bin the bike. A full heat-treatment brings the whole frame back to it's original strength, but I can't imagine anyone doing that to a radiator. I'm also wondering how a radiator would handle the quench part of the T6 heat-treatment.

Used plenty of 2, 6 and 7000 series aluminium's years ago and didn't particularly care for 6061 for the reasons you mentioned, and it was awfully gummy to machine.

Just my experience that I've had far less fatigue cracking issues with aluminium than copper components, particularly tubing in transport refrigeration situations.
We also tried to use non heat treated aluminium for mounting tabs, etc on race cars, just from a fatigue POV.

Copper tube age and work hardens terribly quickly from an annealed state, and unless it's supported properly will fail sooner rather than later.
There seems to be far less issues with aluminium alloy tube, again, just my experience.

My old old mate that worked for JRA and LRA made an aluminium radiator for his 4BD1 110, (he went on a serious weight reduction campaign, the one downside of running a race car engineering workshop )
I wonder how that's lasted ?
He offloaded the 110 a few years back.

BTW, plastic tanks are used on OE applications for cost/ease of production and servicing.