# Goodman-Smith Diagram

1. Aug 7, 2007

### amitjakob

For material fatigue strenght.
unfortunatly google doesnt give any reasonable options, or maybe
someone here will be ready to answer my question for the problems
ive encountered with them.

And the Problem:

a. Stress Ratio
b. Max and Min. Stress
c. Neccesary diameter of the bad in this case with a safety factor 1.7/

So, my attemt was:

a. Stress Ratio is simple Fmin/Fmax , i know this question is kinda mocking the intelligence of the people here, but i though it might lead to the right solution.

b. Max and Min Stress: The table i have shows for that metal allowed limit stress of 870Mpa, the G-S Diagram shows range of 800Mpa to Zero. Solution of my proffesor was Max tension of 950~900MPa and Min 220~260Mpa.

I would say these values are on the same vertical line in the Goodman-Smith diagram, but with no special notance, would appreciate of someone can give a hint.

All the best, Amit.

2. Feb 12, 2009

### Nissen, Søren Rune

I'm going to ressurrect this topic, because I need a little help

In some of my assigned reading, a "Smith Diagram" is explained, but poorly. I get that it's a combination of Wöhler diagrams, but I don't understand how to read it - can anybody help with this?