Magazine Rotation.

[Ithaca37]

I'll repeat to answer:
"All materials exhibit some viscoelastic response. In common metals such as steel or aluminum, as well as in quartz, at room temperature and at small strain, the behavior does not deviate much from linear elasticity. Synthetic polymers, wood, and human tissue as well as metals at high temperature display significant viscoelastic effects. In some applications, even a small viscoelastic response can be significant. To be complete, an analysis or design involving such materials must incorporate their viscoelastic behavior. Knowledge of the viscoelastic response of a material is based on measurement"

"All materials" includes all steel alloys. "Room temperature" means room temperature. It doesnt have to be a "significant" amount to make a difference. What part dont you understand?

I highlighted the important portion of the paragraph you quoted. Viscoelastic response is insignificant at room temperature (and low strain rates) for steels and many other materials. It is insignificant because behavior does NOT significantly deviate from linear elastic response.

I am well aware that creep is present at room temperature. The issue is how significant is the creep rate. For steels that rate is so low that it can be neglected.

Since I am asking you for citations to support your claims, I will provide one of my own. From Material Science and Engineering: An introduction by William D. Callister. Chapter 8 - Failure of Metals

At a temperature substantially below 0.4Tm (melting temperature) and after the initial deformation, the strain is virtually independent of time.

You have been trying to claim that the creep is high enough that it is an important factor in either spring design or in leaving magazines loaded (I am unclear what your argument is exactly). I have yet to see you provide one citation which states that springs operating at room temperature see significant creep.

You are incorrect that time does not play a part in creep.

You volunteered "apologize and amend or remove any incorrect statements".

Please do so.

I am well aware of the time dependent nature of creep. I am also well aware that creep in steel is generally considered insignificant below 30-60% of the alloy's melting temperature.

All I care about at this point is some info on steel alloys which have creep problems at room temp.

If thats all you care about at this point, I suggest another forum.

ALL MATERIALS exhibit it. I can not possibly list ALL of the steel alloys in existance as the list is too long.


Its not a question of if there is creep. Its a question as to if the amount of creep has a negative impact.

If you bothered to read what I said (it is quoted here for your convenience look a few lines above at the part in bold), I stated that I wanted to see examples of alloys which exhibited significant creep at room temperature. I know what creep is and already stated that at room temperature it is so low that it is not an issue. You claimed I was wrong and claimed to be aware of alloys for which creep posed a problem at room temperature (i.e. the rate is sufficiently high so as to be a design issue). I asked to see examples and you have provided none.

I also have yet to see you provide a source for your claim that creep is an issue in magazine springs (or any spring with a room temperature operational environment).

Out of curiosity, what is your background? I am a mechanical engineer.

 

[danez71]

I was doing some back searching and ran across this thread. I didnt realize you were waiting for me to reply.

You have been trying to claim that the creep is high enough that it is an important factor in either spring design or in leaving magazines loaded

No I have not. Quit making stuff up.

I am well aware of the time dependent nature of creep.

But yet you wrote this earlier in this thread.

The amount of plastic deformation that the spring will experience does not change with time under static loading.

You contradict yourself.

)I have yet to see you provide one citation which states that springs operating at room temperature see significant creep.

WHAT?!?! Did you read any of my posts that contained A LOT of sources for you? Seriously.. did you read it and if so, did you understand it... its right here in this thread.

I'm sure you'll now want to argue what 'significant' is so I'll just go ahead and let you set the definition so then I can catch your contradictions later and you wont say that what I come up with doesnt apply.


You have provided 1 little snippit of info that doesnt even include the whole context in which it was written.

I have provided A LOT of sources and resources.

You are either not a mechanical engineer or you selectively read.

You need to go back and reread, stop making things up that i say, and stop contradicting yourself as shown above.