How is carbon attached to aluminium?
03-24-08, 07:51 AM
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How is carbon attached to aluminium?
How is this done on bikes such as the 2008 Specialized Allez Elite which has an aluminium frame and carbon seat stays? What is the nature of the connections where the carbon meets the aluminium? How does the strength of these connections compare to aluminium-aluminium welds?
03-24-08, 07:57 AM
#4
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Seriously though, it's slip-fit, and bonded with adhesive. Same way aluminum dropouts are bonded to CF blades on forks.
03-24-08, 08:01 AM
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And much weaker than an Al to Al weld.
However, though it's weaker than a weld, that's not the right question. The right question is whether it is strong enough for the application. It is.
However, though it's weaker than a weld, that's not the right question. The right question is whether it is strong enough for the application. It is.
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03-24-08, 08:11 AM
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A properly prepared adhesive joint is stronger than the base materials, as is a properly performed weld.
03-24-08, 08:21 AM
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The only issue I have with CF - Alum/Steel/Ti is that temperature differences stress the joint. The amount the material expands or contracts with temperature is different for each material, so any difference in temperature makes the aluminum expand or contract less than the carbon, but because they're bonded together it's stressed until the strain is equal to the difference in expansion/contraction.
This is why you see those pseudo-brick wall facings fall off after a few years. The fake brick expands and contracts at a different rate than whatever it's attached to and breaks the bond.
I've never seen it effect a frame, but it still bothers me.
This is why you see those pseudo-brick wall facings fall off after a few years. The fake brick expands and contracts at a different rate than whatever it's attached to and breaks the bond.
I've never seen it effect a frame, but it still bothers me.
03-24-08, 08:32 AM
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03-24-08, 09:45 AM
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Comparing on the basis of equal bond areas, welded aluminum joints are stronger than epoxied joints. That is my point.
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Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --the tiniest sprinter
Cat 2 Track, Cat 3 Road.
"If you’re new enough [to racing] that you would ask such question, then i would hazard a guess that if you just made up a workout that sounded hard to do, and did it, you’d probably get faster." --the tiniest sprinter
03-24-08, 10:07 AM
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