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I'm starting a book on who will start fitting non-ferous brake discs to their EVs.
Any takers?
The problem with Aluminium matrix discs was contamination of the pads which then caused the discs to break down.

They are also more expensive. So I don’t expect to see these come back any time soon.
 

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The problem with Aluminium matrix discs was contamination of the pads which then caused the discs to break down.

They are also more expensive. So I don’t expect to see these come back any time soon.
Maybe I should have said non-coroding. There are plenty stainless steels available.
 

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Maybe I should have said non-coroding. There are plenty stainless steels available.
I don’t know why stainless steel discs aren’t a thing.

Maybe they don’t have a high co-efficient of friction?
 

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No sure that any production road cars use stainless steels for the friction surface?
Interestingly, stainless steel discs are more common on motorbikes.

It appears that the main reason for use of cast iron on cars is it’s cheap, hard wearing and conducts heat fairly well.
 

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Interestingly, stainless steel discs are more common on motorbikes.

It appears that the main reason for use of cast iron on cars is it’s cheap, hard wearing and conducts heat fairly well.
Ah, so SS brake discs DO exist already!

Nice business opportunity for someone then.

We don't need hard wearing so much on EVs and cheap involves not replacing them due to be corrosion. I doubt if heat transmission varies much between the various alloys of iron.
 

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“The drum brake, as built in the ID.3, provides many benefits, particularly in the field of e-vehicles, for instance a longer service interval of up to 150,000 kilometers.” Due to the closed and sealed system, the brakes in the new VW ID.3 are distinctly less prone to corrosion. Continental Tech Helps New VW ID.3 Drive Connected | The BRAKE Report

The same system for the id4.
Interesting to see how a SEALED drum brake is realised,
.An o ring between the rotating drum and the stationary back plate. A labyrinth seal? A brush seal. It needs to allow for thermal expansion and normal tolerances on runout. Or is it just marketing BS ?????????
 

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Interesting to see how a SEALED drum brake is realised,
.An o ring between the rotating drum and the stationary back plate. A labyrinth seal? A brush seal. It needs to allow for thermal expansion and normal tolerances on runout. Or is it just marketing BS ?????????
I think it’s all relative.

A drum is more sealed than a disc brake from the elements.

I mean it’s not sealed down to 50 metres depth, or rated for space. If that’s what you are asking?
 

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I think it’s all relative.

A drum is more sealed than a disc brake from the elements.

I mean it’s not sealed down to 50 metres depth, or rated for space. If that’s what you are asking?
So it's not sealed at all😁😁😁
 

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“The drum brake, as built in the ID.3, provides many benefits, particularly in the field of e-vehicles, for instance a longer service interval of up to 150,000 kilometers.” Due to the closed and sealed system, the brakes in the new VW ID.3 are distinctly less prone to corrosion. Continental Tech Helps New VW ID.3 Drive Connected | The BRAKE Report

The same system for the id4.
I suspect what Continental VW have opted for is a drum brake with zero self servo mechanical ratio. So it needs a beefy hydraulic cylinder to apply the braking force, no problem. This kind of brake would be rubbish as a cable operated handbrake for all but gorillas bit it's got a powerful motor for that function (this fits in with modern interior styling and automated actuation). The benefit of the non servo action is much improved ESP dynamics, something that ordinary drum brakes struggle with. YES, locks like a good solution overall.
 

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I'm starting a book on who will start fitting non-ferous brake discs to their EVs.
Any takers?
Other than ceramic there's not much out there that works as well as cast iron. Not holding my breath for non-ferrous metal discs.

How about liquid cooled front drums - could use the 'waste' heat to warm the battery pack in winter or supplement the cabin heater.

No complicated engineering or extra things to go wrong there.....:sneaky:
 

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Other than ceramic there's not much out there that works as well as cast iron. Not holding my breath for non-ferrous metal discs.
Imagine if there was a non-contact method to stop a car, that had no moving parts and even captured the energy for later use? :unsure:
 

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What's wrong with ceramic then?

Increased demand should drive the cost down.
They only work when they are maintained at a high temperature.

So not very good when you hit the first roundabout after a long dual carriageway cruise.

Excellent for the track though.
 

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But seriously, if all our EVs have motors that can work in reverse - why do we even have friction brakes?
 
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