Strength of carbon fibre componants

[Just_a_fan]

Suspension arms on F1 cars use blade connections at the tub end. These are flexing connections and so bending moment is experienced by the wishbone.

The clip of Hamilton / Mass at Monza wasn't the wishbone breaking - it was the track rod (the steering arm) - and so somewhat weaker in the first place.

[xxChrisxx]

Suspension arms on F1 cars use blade connections at the tub end. These are flexing connections and so bending moment is experienced by the wishbone.

Definitely not going to be broken with a kick then.

[bhall]

You likely won't break it into two pieces, but you will break it.

viewtopic.php?f=6&t=9447 (wishbone)

viewtopic.php?f=6&t=11557 (pushrod)

Those are excellent threads.

[NathanOlder]

The Video with richard hammond just shows you how strong carbon fibre is, when used the way it is intended. In the video with Hammond, the carbon fibre shaft copes with about 3 times the torque of a steel draft, I wonder what the results would be if you had the shafts held at each end and put weight on the middle of the shaft, which would be stronger then?

[flynfrog]

You likely won't break it into two pieces, but you will break it.

viewtopic.php?f=6&t=9447 (wishbone)

viewtopic.php?f=6&t=11557 (pushrod)

Those are excellent threads.

those were the threads I was looking for.

edit* an no way you can kick hard enough to break that. even if the laminate was half that thick there is enough uni in there to more than stand up to the small amount of force a mere human can provide

[bhall]

I never said they aren't robust. You've just underestimated human strength.

When it comes to kicks, "they can obviously generate more force, since there's more body mass behind it," Bir said. After looking at kicks from several different fighting styles, they found that experts could generate up to 9,000 newtons with them, equal to roughly a ton of force.

If a suspension member can withstand that force for no particular reason, the suspension member is too heavy.

[flynfrog]

I never said they aren't robust. You've just underestimated human strength.

When it comes to kicks, "they can obviously generate more force, since there's more body mass behind it," Bir said. After looking at kicks from several different fighting styles, they found that experts could generate up to 9,000 newtons with them, equal to roughly a ton of force.

If a suspension member can withstand that force for no particular reason, the suspension member is too heavy.

that would be right up there with the 2000psi I posted earlier. Its not that its taking it for no reason. the direction the laminate might be weak in would not be bending it the long it would be bending the short way My guess is there is a bunch of uni in it to make it strong enough in the loads its meant to see. These will also make it strong in a bending direction. Don't forget that the A-Arms are also flexure joints so they are taking the load of the car in bending.


On a side note when does racing start so we can quick discussing whos dad can beat up our A arms and start talking about cars again.

[bhall]

Hey, I live in Texas now, and, as such, I've decided to embrace the time-honored local tradition of engaging in pissing contests. Apparently, it's a "man" thing.

I've never said that F1 wishbones are absolute twigs. However, I don't think they're what you want them to be, either.

Not to sound like a broken record, but there's absolutely no need in the world for a control arm to be able to withstand the force we're discussing. The suspension loads are carried by the push/pull rods, any bending at the chassis is minimal, and their functional lifespan is very, very short.

With that in mind, why would it make sense to build a control arm that's stronger/heavier than necessary?

This seems very obvious to me, so that probably means I'm missing something.

[Nando]

Note – the original assertion was that if you hit it in the wrong way it will break easily. So, the case in which it's dragged around in an odd way is exactly the case being talked about.

But did the carbon break in the Hamilton case or did the whole suspension mount get dragged out of it´s position.

Obviously the carbon part will be weaker in one direction but that would be the same if it were made from steel aswell.

the issue is the "weaker" seeing as it can´t be weak in any way because then it would not absorb energy like it should.

[flynfrog]

Hey, I live in Texas now, and, as such, I've decided to embrace the time-honored local tradition of engaging in pissing contests. Apparently, it's a "man" thing.

as a former Midwesterner I will be more than happy to write my name in the snow.

You are assuming the A arm is built to strength not stiffness.

I would guess that "you" cant break a 2X4 by kicking. I would assume that an F1 a-arm is stronger than a 2x4.

[bhall]

Well, you know what they say about a dog that don't pee on trees...

I think it's hardly fair to compare timber to carbon fiber in this scenario. Timber isn't nearly as brittle.

(Is it just me, or has the name of this thread changed a few times?)

[thisisatest]

it is possible that, in engineering the wishbone to be strong and stiff in the intended directions, there is a side effect of sufficient strength to take a karate kick. composites have much less strength in directions it is not meant to handle, but it has SOME strength in those directions...

[Nando]

It must have some strength in other directions. It´s an F1 car that is designed to hit stuff at near top speed so everything has to be scaled for that.

Everything except the monocoque is energy absorbing, if it breaks by a simple kick it will hardly absorb anything.