Boron steel in car panels

[mike 109444]

Mention has been made in the past on forum of Boron steel being used on modern cars but how does one tell if that is what has been used? I understand that there are issues trying to weld it (should be mig brazed iir) Reason for question is daughter has clunked her 61 plate Audi A4. She caught the door + wheel arch as she pulled out of parking space in supermarket catching one of the steel post. May be more damage but only looked at night in rain so quick glance!

 

[Wendelspanswick]

Mention has been made in the past on forum of Boron steel being used on modern cars but how does one tell if that is what has been used? I understand that there are issues trying to weld it (should be mig brazed iir) Reason for question is daughter has clunked her 61 plate Audi A4. She caught the door + wheel arch as she pulled out of parking space in supermarket catching one of the steel post. May be more damage but only looked at night in rain so quick glance!

I think the original panel would have been MIG brazed in if it is boron so if you can find a panel joint... not easy I know on modern vehicles!

 

[TechnicAl]

Its thinner.......but you probably need something to compare it against

 

[mike 109444]

Its thinner.......but you probably need something to compare it against

Well she compared it to to a steel post and it lost !

 

[mike 109444]

I think the original panel would have been MIG brazed in if it is boron so if you can find a panel joint... not easy I know on modern vehicles!

Hoping not to have to weld but maybe pull dents with slid hammer and pins but would like to know "just in case"

 

[F.J.]

When I worked in a commercial vehicle repair shop, panel adhesive was mainly used on side panels on vans and rear panels and rear quarter panels on truck cabs. On the vans the on,y area to be welded was the sill. Quite good stuff and speeds the job up no end. I went to Thatchem once as they had an open event on and a couple of guys told us that due to cuts, manufacturers wouldn't give them cars to work out repair methods so they would rent a hire car and cut it to pieces and 'repair' it to produce repair methods and times. How true that was I don't know

 

[hotrodder]

I can't see a door skin or wheelarch being a likely candidate for UHSS/boron steels. Structural bits like door impact bars, some sections/layers of door pillars, screen frames, sills etc yes. According to http://www.ika.rwth-aachen.de/images/veranstaltungen/2008/iac/08_thyssen_krupp_hilfrich.pdf 35% of the steel in an Audi A4 is soft/deep drawing grades, 36% is conventional HSLA (been used for structural bits in cars for eons) and the remainder is a mix of posher/harder stuff with 11% being hot forming UHSS stuff. Somewhere on the internet there's probably more indepth info on which panels are made from what flavour usually depicted with colour keyed drawings like

 

[mike 109444]

Ta HR

 

[pedrobedro]

I went to Thatchem once as they had an open event on and a couple of guys told us that due to cuts, manufacturers wouldn't give them cars to work out repair methods so they would rent a hire car and cut it to pieces and 'repair' it to produce repair methods and times. How true that was I don't know

Like Thatcham couldn't afford to buy a couple of bodyshells or don't have enough insurance contacts to blag a write off or two.

 

[bc30se]

You think they care?

 

[Chop 13]

When and if you weld the pins to pull it out Mike, they won't weld to boron steel and just fall off.

 

[mike 109444]

When and if you weld the pins to pull it out Mike, they won't weld to boron steel and just fall off.

That is Thanks Chop 13 interesting, so Boron steel won't take the normal mild weld process. Think it's just as well the bit I will need to do seams to be outside of the boron steel zone. but may come across the issue in future maybe.

 

[BrokenBiker]

http://www.bodyshopbusiness.com/working-with-boron-steel/

this should give you some idea about boron steel in cars. it does say on there that some manufacturers allow mig welding but be weary of the heat affected zone...

i only googled it because i was sure boron was used to produce the green flares in fireworks and wanted to check i was right lol

 

[TechnicAl]

When and if you weld the pins to pull it out Mike, they won't weld to boron steel and just fall off.

What did you try?

 

[Chop 13]

2015 Vauxhall Astra a-post, tried to spot some keys on to it where the lower hinge is. It's double skinned but only the outer skin was dented.

 

[mike 109444]

http://www.bodyshopbusiness.com/working-with-boron-steel/

this should give you some idea about boron steel in cars. it does say on there that some manufacturers allow mig welding but be weary of the heat affected zone...

i only googled it because i was sure boron was used to produce the green flares in fireworks and wanted to check i was right lol

Interesting reading especially about the lack of protection due to not being able to galv because of heat affect! Think this material will make some home repairs more challenging in the future as these become the "old cars" in need of a patch.

 

[TechnicAl]

Boron steel is weldable. It should have been OK

What happens is heat generated weakens it. Not massively but enough to make a difference.

They take advantage of the increased strength by using thinner sheet which reduces weight.

 

[Chop 13]

Soon as I put the bar through the keys they fell off and left holes in the outer skin!!

 

[TechnicAl]

could it be the thinner material?

 

[pedrobedro]

could it be the thinner material?

That and the heat affected zone should explain the pins pulling out.