- #1
pete
- 72
- 5
I have a question about the nature of steel. As I understand it to measure the bending strength of a rod of steel there is the yield strength and the tensile strength. On a plotted line for the elastic modulus there is the elastic part to start. Anywhere on this part of the graph a load can be applied and the rod will deform a corresponding amount but return to it’s original position afterwards. After a certain amount of weight or force you hit the yield strength and the rod will no longer return to it’s original shape. There are some other ways to measure the strength of the rod but my question only refers, I think, to these two.
I have a stainless steel part, a 300 or possibly a 400 if needed and a load is being applied that is well below it’s yield strength. So every time the mechanism is activated the steel part transfers the load as it should. Under load it will bend a tiny amount then return to its original form. So according to this all I need to do is make it large enough to have it’s yield point above the force applied and it’ll work forever, but what if that force is applied for extend periods, like over night or repeatedly at a high frequency for years? If it’s below the yield point dose it make no difference? Or is there an accumulative strain that will eventually leave the part misshapen.
The force involved is pretty low, the part is 12mm by 10mm with a bolt being tightened by hand no more than 30mm from the fulcrum on the longest side. The part moves about 1mm then is braced but the space is tight and if the part was to bend over time about 2-3mm it would mean it no longer worked. This description isn't really really needed for the question but if it paints a picture maybe it’ll help.
I have a stainless steel part, a 300 or possibly a 400 if needed and a load is being applied that is well below it’s yield strength. So every time the mechanism is activated the steel part transfers the load as it should. Under load it will bend a tiny amount then return to its original form. So according to this all I need to do is make it large enough to have it’s yield point above the force applied and it’ll work forever, but what if that force is applied for extend periods, like over night or repeatedly at a high frequency for years? If it’s below the yield point dose it make no difference? Or is there an accumulative strain that will eventually leave the part misshapen.
The force involved is pretty low, the part is 12mm by 10mm with a bolt being tightened by hand no more than 30mm from the fulcrum on the longest side. The part moves about 1mm then is braced but the space is tight and if the part was to bend over time about 2-3mm it would mean it no longer worked. This description isn't really really needed for the question but if it paints a picture maybe it’ll help.