Grade 10 bearings

[Sam]

(01-11-2015, 02:19 PM)nfmisso Wrote:  

(01-10-2015, 09:47 PM)Sam Wrote:  Nigel; you don't actually address any of my questions. Just telling me I'm wrong because you're better qualified than me isn't particularly helpful.

Sam; a proper response would be several hundred pages of detailed technical information that is way beyond the scope of this forum. You have given no information as regards to your educational and experience back ground, so I have no idea where to start. If you are really interested, start by reading some papers on Hertzian contact stress, and R.E. Chinn's paper: "Hardness, Bearings, and the Rockwells," published in : Advanced Materials & Processes, Vol 167 #10, October 2009, p 29-31.

I read R.E. Chinn's paper: Hardness, Bearings, and the Rockwells, and found that, although historically interesting, it didn't really tell me anything I needed to know.

I did some searching to refresh my 35 year break since A-Level Engineering Science, and realised that the practical experience I've had since of tool hardening etc. has somewhat lead me astray.

As I'm not looking for a complete understanding of the stresses within a bicycle wheel bearing, just a good idea of what materials will best survive them, I really don't need a PhD in Contact Mechanics, or even your several hundred pages of technical info., just a simple reminder that Toughness relies on Plastic deformation to avoid fracture, and thus would replace Spalling with Denting which would be as bad or worse, and that in standard Engineering terminology Hardness is a measure of resistance to Plastic deformation. not Elastic deformation (as in common usage).
Simple (or just Simplified ;¬)

You were (of course) right that there is no disadvantage in Harder ball bearings, but can you, from your obviously advanced understanding of the stresses involved, tell me if there's any advantage in Case hardening as opposed to through hardening ?