"Metals and alloys that exhibit very low solubility for interstitials (such as aluminum-, iron-, nickel-, and cobalt- base alloys) are not readily diffusion bondable."
Thanks for the link, Peter. I never thought about the relationship between solubility and diffusion bonding. It makes some sense, though; low solubility should lead to low diffusion coefficients.
We have different perspectives on diffusion bonding. You imply that using interlayers or vacuum makes a process exotic, but I think those things are normal. And those aspects are part of the reason that I think of diffusion bonding as expensive.
Not that any of this has anything to do with bikes. Well, maybe one could make a stronger bike by diffusion bonding the frame. No residual stress, no heat affected zone, etc. Time for a patent! :^)
Well, the original debate was over whether BB bearing wear was from fretting/galling or cold/diffusion bonding. My comments(context) weren't really about the economics or even feasibility of cold/diffusion bonding, just on the likelihood of it being the wear mechanism in a BB bearing.
Headset bearings can deteriorate from micro-welding. I doubt that bottom bracket bearings do. More likely bottom bracket bearings deteriorate from intrusion of water and grit, and from loss of lubrication.
btw, since titanium so readily passivates, [oxide layer], perhaps you'd like to inform the class on why exactly it still manages to stick to itself so readily.
I think if either one of us really knew the answer to that we'd be wealthy men.
(Of course, my testimony is suspect. I could be nothing more than an out-of-control class project in abnormal psychology being conducted without the teacher's knowledge over at St. Therese by a clique of giggling Catholic schoolgirls.)
Hmm. That would explain why you still haven't installed my tire savers...
btw, since titanium so readily passivates, [oxide layer], perhaps you'd like to inform the class on why exactly it still manages to stick to itself so readily.
I think if either one of us really knew the answer to that we'd be wealthy men.
