Aluminized Exhaust Tubing

I need to replace my exhaust system, so I've been wondering about aluminized exhaust tubing. What exactly is the aluminizing? Does it give off the same sort of fumes as galvanized steel when welded on?

 

Muffler shops around here use it all the time. They MIG weld on it with no precautions. So do I. However, were all psychotic. Wonder if there's any connection??? Hmmm...

 

Last time I welded that kind of tubing, I grinded little bit of it away, and after that welded seam. After it had cooled off, I painted it with paint that withstands the heat. Not the cheapest one; buy better, Plastikote or VHT or such. (No, I don't know if you have those brands in US...) Year after that, aluminized layer had rust on it, but painted part of tubing did not...

 

No it's not any more hazardous to weld than any other mild steel. It's good stuff for what it's made for. The welded seam and any welds added to it will rust over time if they are not protected with header paint but it takes years. I like to get a brushed aluminum look by buffing it with scotch-brite. It only takes a few minutes but lasts a long time.

 

From the site www.I-car.com:
<TABLE cellSpacing=2 cellPadding=2 width=108 border=0><TBODY><TR><TD vAlign=top align=middle><!--fig 2-->
</TD></TR><TR><TD>

Figure 2-This corrosion hot spot was caused by welding a hanger bracket onto an aluminized exhaust pipe​

</TD></TR></TBODY></TABLE>[SIZE=+0]Another challenge is that when aluminized exhaust parts are welded, the heat in the weld zone will burn off the aluminized coating creating a corrosion hot spot. This will lead to premature failure of the part from corrosion through and around the weld. In Figure 2, you can see the corrosion starting on a new aluminized exhaust pipe where a hanger bracket was welded to it. These exhaust parts are new enough that the paper sticker, with the part number, is still on the tailpipe, yet there is already significant corrosion around the weld zone where the bracket was attached.[/SIZE]
Not an issue w/carbon steel, but...
[SIZE=+0]There are also some additional health concerns when welding stainless steel. The nickel in stainless steel can cause asthma and cancer. The chromium can cause cancer, sinus problems, and &#8220;holes&#8221; between the nostrils. A welding respirator is required when welding stainless steel.[/SIZE]
If the aluminum coating contained any other metal elements, then I'd check on those heath risks when it came to welding. At least use ventilation and grinding back is a good precaution.

 

you can also buff the aluminized tubing! it will shine up real good...

 

I was trying to weld on the tailpipe of my daily last night, when I tried s****ing away the coating, It looked like copper underneath. I couldn't fit a grinder in there, so I gave up on being lazy and found the right sized bolt to repair the hanger the correct way.

Any ideas about the gold color under the grey?

 

Good deal. I'm a total wuss about stuff like this, but I've messed myself up pretty good by not paying attention to the warning labels.

 

Depending on what year and model it could be stainless steel. It's a lower grade stainless than sinks and such but it is used almost exclusively now a days.

 

'88 Chrysler 5Th Ave. I had some headers on another late model that were stainless, maybe 304 grade?, but had surface rust and were grungy looking. I tore a hole in them and a muffler shop welded them up somehow.