Finding Stress Concentration Factor K for Chamfered Joints

[patrickv]

Hello, I have a rod of two different diameters and I'm trying to find the stress concentration at the chamfer between the two diameters. I understand how to find the stress concentration factor, K, if the joint was a fillet (using r/d and D/d to find K in the appropriate table). However I can't find any way of getting K for a chamfered joint. Please help point me in some direction. Thanks so much. I've attached a quick diagram showing the filleted and chamfered versions of the shaft. The chamfered one is the actual piece I'm trying to find K for.

 

[Brian_C]

I would make a model in SolidWorks or some other CAD program, and do stress analysis. Should be pretty easy.

 

[FredGarvin]

There is no reference in either Peterson's or Roark's for this. I do remember Q_Goest having the same post a year or so ago. You may want to do a search for that thread. I can not remember what conclusion he came to. I would start by treating it as a very small radius, which in reality is the truth. You will not machine a perfectly sharp corner.

 

[minger]

I would make a model in SolidWorks or some other CAD program, and do stress analysis. Should be pretty easy.

Chamfers are by definition sharp corners. Getting real stress results from a sharp corner numerically is quite a challenge, dare I say impossible. It's hard enough getting real stress numbers in a fillet where you can actually get grid to follow the surface.

You may have to assume a filleted case and take some sort of worst conservative case.