Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
(OP)
Hi All,
I really need some help understanding bending stresses and stress concentrations in Morse Tapers. Specifically, I'm trying to understand the influence of a slot (and orientation of the slot) in the female component of a Morse Taper when the male component is subject to bending. I've created an illustration depicting the scenarios I'm trying to wrap my head around in hopes someone may be able to point me in the right direction. Most Morse Taper information I could find deals more with hoop stresses, friction, dissociation, etc., but not bending and modified geometry/stress concentrations in the female component.
I've searched the great forums here, reviewed Peterson's Stress Concentration Factors, looked through many Materials texts and searched the peer-reviewed literature for similar instances. The closest I could find was a finite element model of a hip replacement that utilizes a very similar design (Analysis of the stem-sleeve interface in a modular titanium alloy femoral component for total hip replacement, Kurtz, 2001). They reported that maximum stresses on the male component occurred at the BOTTOM of the taper junction when oriented as shown in the representation second from left (slot centered in view).
Can anyone help me understand how the slot geometry and orientation on the female component might influence the stresses on the male component when the male component is subject to bending?
Thank you so much!





RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
Just building a house of cards, but if titanium is used for strength and basic corrosion resistance, it's reputation for galling still requires special efforts with coatings and what not in sliding applications.
http://www.youtube.com/watch?v=DHGCvJjat1E
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
Ted
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
We know there is micromotion based on fretting that has been documented in implants that have been removed from people for various reasons (infection, loosening, pain, etc.) That's an interesting comparison with the fitted wrist pins...2500 RPM...yikes! The biomechanics world assumes a hip will be "cycled" ~2 million times/year.
Unfortunately, I'm stuck...I can't find any way to estimate the stresses on the male component in the taper or the influence of the slot. Is it possible the slots actually act as stress relievers?
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
Ted
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?
So, it a slot were cut in the side of the Morse taper, but the sideways force remains the same, there is now a shorter lever arm (the first point of resistance to stretching is about half-way through the Morse taper sleeve), and so the sideways forces are greater.
If the slot is present, but is rotated so the slot is at the far side of the morse taper, the resistance to stretching the top of the Morse taper is resisted also by the wall of the taper.
The slot reduces (slightly) the area on the base plate able to touch the Morse taper (and so psi of the force on the baseplate wall may increase from that of a solid Morse taper sleeve).
In any case of any slot at any direction, however, the Morse taper resists expansion across the slot by being wedged into the tapered hole in the baseplate. Therefore, the least amount of force (stress) into the baseplate is with no slot all - if that were possible.
RE: Bending Stresses/Stress Concentrations in Morse Taper w/Slotted Female Component?