This is exactly what I was looking for. If the design factors and other corrections are built into the curves, then it makes total sense that they are quite different than experimental S-N curves. Thanks for replying and providing a reference to a document that provides additional explanation.
I am trying to reconcile the considerable difference between the ASME S-N curves and what you find in typical machine design textbooks (e.g. Shigley).
In the texts (e.g. Shigley), S-N curves are constructed using S_ut. The endurance limit (N=10^6) is 0.5*S_ut for lower strength steels. The...
The particles were yellow on the optical scope so I guess the EDS Nitrogen signature was not erroneous. Makes sense as well that they are dark on the BSE detector due to relatively low average Z.
Unless someone would like to chime in with information on how titanium nitride stringers on this...
All,
I am going to investigate the white particles further to try and discern between laves phase and carbides. We were seeing high C signals, but looking at our matrix readings I am starting to think we may have some carbon surface contamination. I'll ultrasonicate it briefly in alcohol and try...
MagBen and EdStainless: I am unfamiliar with the acronym COA. We plan to do spark OES to get accurate bulk composition data once we get approval to excise and flatten a sufficiently large piece of material. I have attached a BSE (compositional contrast) image of the LT plane. The small...
The average hardness is a little over 300 HV.
We haven’t cut test strips for mechanical testing yet. That may not even be an option (explanation below).
Fatigue is definitely a possibility. This is 0.030” wall 2”OD tube and failed at a 90 degree bend (welds are all remote from failure). It...
Anyone here work with 625 regularly that could comment on whether a microstructure we are seeing is normal/typical?
We have not etched yet and are using BSE and EDS on the SEM to differentiate phases in a polished specimen. We don’t have EBSD so the identification of phases is a bit loose. We...
Does anyone know where I can find documentation on how SOLIDWORKS calculates the transverse shear stress in beam elements. I am used to the tau=VQ/Ib formula.
SW appears to use a shear factor, but does not provide documentation on how the value is derived or used to calculate the maximum shear...
I am trying to analyze the stress in a simple link (straight link, pins at both ends) that is part of a mechanism (planar analysis).
I have solved the planar kinematics/kinetics equations (rigid body motion), so I know the reactions at the pins and accelerations (linear and angular) at the...
I understand the definition of the resultant condition (RC) for MMC and LMC, but what I fail to understand is how they are applied. A search of the 2018 revision found no hits for resultant condition outside of the table of contents and the figures in section 5.
Using an external feature at...
Excellent points.
I am trying to understand the implications of these tolerances w.r.t. mating parts (fit). I was just using the position VC to visualize the hypothetical mating boss. It would appear the size and positional tolerances are sufficient to ensure the fit of a mating component. The...
Thank you both for the replies.
I was just thinking about the possible acceptable configurations incorrectly. I was assuming that the bonus added to both would push the hole inside the position VC surface while still remaining acceptable by the axis method. I have it in my head that as a...
I am having a bit of confusion around how to interpret a feature that has both position and perpendicularity tolerances attached to it. I get that the position control will, by itself, restrict the orientation and my understanding was that an additional orientation control was only added if...
