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Fabulous resource shots. Thank you.
Now I understand the brake and windshield washer fluid reservoir locations better.
That right rear tire seems to have taken more than its share of abuse, though!
 

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4C

Fabulous resource shots. Thank you.
Now I understand the brake and windshield washer fluid reservoir locations better.
That right rear tire seems to have taken more than its share of abuse, though!
I shot these pictures last year during 4C education. This car was one of the test 4C .
 

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Interesting that all the rear of the chassis appears to be metal ...unless that is because this car is a prototype?
Pete
 

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Interesting that all the rear of the chassis appears to be metal ...unless that is because this car is a prototype?
Pete
Front and rear crash struture and engine mounting points are all aluminum.
Only the middle bit, the "tub" from firwall to front of cabin,is carbon fibre.
 

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Front and rear crash struture and engine mounting points are all aluminum.
Only the middle bit, the "tub" from firwall to front of cabin,is carbon fibre.
i wonder how much of that rear metal structure relates to the overall chassis rigidity? A say this because the rear suspension attaches to it.
Pete
 

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i wonder how much of that rear metal structure relates to the overall chassis rigidity? A say this because the rear suspension attaches to it.
Pete
Rigidity, lightweight, energy dissipation (crash absorption), repairability, lower cost, and modularity (for future chasis variation) were all considerations, from what I have read.
The carbon monocoque flexes to a different degree than the aluminum frame.
Downside is that the connection between CF and aluminum structures need annual inspection by Alfa service department.
 

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"Downside is that the connection between CF and aluminum structures need annual inspection by Alfa service department"

Probably worried about the possible onset of galvanic corrosion in the aluminum, as gr/ep and aluminum in contact needs to be separated by some sort of dielectric material so that a "battery" isn't created when everything gets wet, esp if salt is used on the road in the winter.

Thus the evidently required inspections.

On one airplane I helped design, some of the gr/ep and aluminum structure in joints was separated by Kapton film. In other areas, the gr/ep structure was attached to titanium structure, titanium metal being used in part because it doesn't create a battery when against the carbon composite material.
 

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"Downside is that the connection between CF and aluminum structures need annual inspection by Alfa service department"

Probably worried about the possible onset of galvanic corrosion in the aluminum, as gr/ep and aluminum in contact needs to be separated by some sort of dielectric material so that a "battery" isn't created when everything gets wet, esp if salt is used on the road in the winter.

Thus the evidently required inspections.

On one airplane I helped design, some of the gr/ep and aluminum structure in joints was separated by Kapton film. In other areas, the gr/ep structure was attached to titanium structure, titanium metal being used in part because it doesn't create a battery when against the carbon composite material.
You're talking about electrolysis, which is a big problem in boats. It happens with any dis-similar metals, some worse than others. Boats are the worst as they live in water. Cars take so long most don't even know about it.

Carbon fiber is a conductor of electricity. Not sure if it will break down like metal but the aluminum sub frame certainly will.
 

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And I continue to learn things, interesting thanks :)
Pete
 

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"You're talking about electrolysis"

Yes, that is right. Interesting that Alfa is insisting on inspections of the joints, as if they don't quite trust what they have done. I'd be leery of driving a 4C in the winter where salt is used on the road, not that I figure that many would take such a chance of driving a 4C on slippery winter roads.

Always a big problem with the new use of Gr/ep composites. The aircraft companies know pretty much how to protect it, though. For example, the 777 horizontal stabilizer is Gr/ep, has been used on that airplane for several decades. Same with some Airbus models.

Luckily, our sailboat is all fiberglass with an outboard motor, so even though the boat sits in saltwater all year, there is no problem with electrolysis. The mildly acid rain does slowly try to dissolve the zincs on the outboard motor, even though it sits kicked up out of the water almost all of the time.

Alfa had the problem of having stainless window trim clips which cut into the painted body metal, thus creating areas of galvanic corrosion in many models. Now, everything is glued on instead.
 
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