Thread: KVA tubing?
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Old 10-19-10 | 05:04 AM
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Falanx
THE Materials Oracle
 
Joined: Feb 2006
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Bikes: Univega Alpina 5.1 that became a 5.9, that became a road bike... DMR TrailStar custom build

KVA aren't new to the market, they've been trying to sell their new technology to various interested parties for some time, but the Ford snub was a quite a blow, moreso, a stupid and ill-thought out one on Ford's part.

As a general rule, most steels are more durable and fatigue resistant than titanium alloys. Both have actual definable fatigue lives, unlike aluminium and magnesium alloys, and carbon fibre composites. Steels lives are higher than titanium alloys of the same strength level, and most steel alloys are readily hardenable to higher strengths and toughnesses than titanium alloys. Where titanium sells is specific strength. But that's another discussion.

A) They interest me, not so much in their exact present behaviour, but their chemistry, which seems to be a littlemore difficult to determine by guesswork than Reynolds 953. What alloy(s) is/are being used to make their line to bicycle tubesets, and what possible chemistry improvements could potentially be made still for reasonable ROI? The initial intention was to manufacture tubing that would be as low-cost as possible, but the thing about steels is that the slightest addition of another element that does not alter the unit price significantly can have profound effects on thermomechanical behaviour.

B) Stiffness is one of the most hotly debated topics still in framebuilding. It's not even the right word, but we make do with it. Stiffness is really a solid material mechanical parameter. 'Rigidity' would serve us better to define how compliant a frame is or isn't. But: Do you really seek maximum stiffness? How stiff is too stiff? What tubeset dimensions are available - this above all else has the most effect on a tubeset rigidity. Taking two identically drawn tubes, one in a titanium alloy and one in a steel, the steel will have a higher rigidity, as steels' Young Modulus is about 195% that of titanium and its alloys.
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