What is Creep: Definition and 41 Discussions

I'm sorry I'm uploading lots of images because I don't know how to write equations here. PROBLEM DESCRIPTION I have to solve this problem: Figure P3.6: MY SOLUTION I did this: THE CORRECTION I got this as a correction: - Don't use the middle line in figure P3.6 in my calculations. -...

What I do not get is why should a stress much lower than yield point cause deformation in a material? If temperature is high intermolecular attraction is reduced and thus even low stress can deform things. But if it is low Then a force lower than yield point should be less than intermolecular...

I'm doing static analysis. I have already set up all the prerequisites, preprocessors such as material addition, sectioning, defining boundary conditions, and displacement. However, I'm not getting the results. Please suggest anything. Kindly find the attachment. regards

Hello, I am a civil engineer and have been working on concrete creep phenomenon for several years now. After reviewing a large amount of literature on related topics throughout this time, some interesting observations have emerged, and they have formed the idea that the material creep mechanism...

I wanted to dig deeper on previous question regarding Normal forces and banked turns vs. inclined planes. Intuitively, when a car going around a banked turn is going faster than the "tuned" speed (i.e., the speed at which no friction is required to keep it on the track), it will need friction...

Just wish to know if there are GOOD EXAMPLES out there on the topics above. I am particularly looking for thermal creep using ANSYS Mechanical Workbench ... Thank you much.

Can someone explain the terms viscoelasticity, creep and strain and their relationship to each other? Especially the difference between creep and strain. Any help would be greatly appreciated, thank you!

I'm doing some spring endurance test. If the spring is exceeding its cycles limit and causes fatigue failure, how normally the spring constant changes? For example, after the expected limit cycles (lets say 2million load-unload cycles), will the spring constant gradually decreases? or...

Hello, recently I became interested in some basics of material science and there was one thing that I did not really understand. What is the difference (or what are things in common) between creep and strain rate sensitivity? I read about it in connection with indentation. - To measure the...

I'm helping to install an above ground pool. We leveled the ground. This left a 22" berm on the high side. We left an extra foot of space between the berm and the pool edge, but we're concerned it's going to eventually creep down hill and put pressure on the side of the pool. How big of an...

Why is the actual value of temperature, at which alloy is at a risk of creep, higher than the expected 0.3 (or 0.4) of melting point?

1. Problem statement A steel rod supporting a stress of 8000 psi at 1000 ◦ F is not to exceed 5 % creep strain. Knowing that the steady-state creep rate can be expressed by an equation of the form ##\dot{\epsilon}_{s}^{C}=B|\sigma |^{n} exp \left(\frac{-Q}{kT} \right)## ε⋅, strain rate B...

ANSYS can be used to model creep in a number of different ways. If you are designing to ASME Section VIII, Div., 2 you might have to verify that your design meets the "shake down to elastic action" criteria. Basically, that means that the strains do not continue to increase over the number of...

To prevent grain boundary sliding so that creep is less likely to occur, usually engineers would design components of larger grains or have columnar grain structure to prevent grain-boundary sliding. Why this two method can prevent grain-boundary sliding? For columnar grains, would they be more...

Hi all, As suggested by the title, i wanted to know as to why creep is a function of time. Since for any component the load and temperature are constant, still it creeps. What happens there at microscopic level? Why does the solid component continues to deform slowly under constant load and...

So I'm looking through some material on creep for one of my courses. There is a graph of strain ε vs Time, t. Consisting of Primary creep, steady-state creep, and tertiary creep. I pretty much can follow that and understand why the graph looks the way it does. However there is another...

I am looking for some information on how to calculate fatigue life for materials at temperatures elevated into the creep realm. ASME Sec 8 Div 2 describes how to do this for carbon steel below 700F and stainless below 800F, but I am interested in temperatures > 1000F. I am performing an FEA...

Homework Statement A 10 inch long 316stainless steel structure is in service at 1200°F. The maximum creep elongation in service permitted is 0.05 inches in 500 hours. The minimum creep rate vs. applied stress is known at 1100 and 1300°F and given by the following equations σ =...

Dear all, I am Levy , I am glade to take part into physics Forums, I hope I can share my know with everybody and study from you, Thank You! I test the PET of creep deformation recent days, who has some reference about this aspect. Thank you

Hi all, new to the thread due to a lab report being in tomorrow! Basically if anyone could shed some light on how to calculate secondary creep.. In uni we have undertaken a lab report on tin/lead solder and given two formulaes to calculate the ε. ε = αlnt + c ε = βt^m + c Temperature...

I tested creep in the labs at univeristy, one thing i am confused about is, we made a graph of the extension against time. Taking the gradient gives us E or secondary creep rate. Homework Statement The equation for this (without using gradient ) is, E= A stress^n e^-Qc/RT A and n are...

Deformation-Mechanism Maps, The Plasticity and Creep of Metals and Ceramics, by Harold J Frost, Dartmouth College, USA, and Michael F Ashby, Cambridge University, UK. Creep is a slow plastic flow of a material, and plastic flow is a kinetic process...

Hello, I am developing an analytical approach to determine the creep constants of a constitutive model for nickel-base superalloys. I require creep strain versus time data to valid my approach. I've searched through literature and have found very little usable data. I need creep...

Hello Is there some data or some formulas to calculate how much does steel wire creep at a constant stress? If I have, for example, a 1 m steel string with 1 mm diameter under a constant tension of 1000N at a temperature of 20C, how much does it creep or lengthen in a year? I tried...

Hi all, I have a question. Does exists a software that is able to calculate creep and stress relaxation of a model of springs and dampers? Is Matlab/Simulink able to do this? Thanks in advance.

I was doing a project to test for creep in materials, and one of the things that I wonder would be the fact that the translucent plastic would start to turn opaque when it starts to strain, just like why plastics when bent starts to turn white where the bend is. Why is this so? I know creep is...

How does shot peening help improve fatigue life, or rather, how does the compressive surface stress imposed help improve fatigue life? How does materials having high elastic moduli and large grain size prevent creep?

I don't know if the answers by me are correct or not to these questions. Can someone please check them and give me some suggesstions. thanks QUESTION 1 Explain the distinctive stages of a creep failure. (5 marks) ANSWER Creep is the slow deformation of a material when it is under...

Hi all, I'm trying to crack what is admittedly a homework question. I don't necessarily want you to just spit out the right answer for me, but if you could point me in the right direction it would be appreciated. A shelf for a hot air dryer is to be made from acrylic sheet. The shelf is...

Hey Quick question. I am trying to model creap in an FEA or similar package, but what package should i be using and how complex is this? I am using just a BS Lead Test Piece, which does lead me to ask - Does anyone know the standard dimensions of a test piece, i was using lead, and can...

Hello, With creep, could anyone please give me any information with regards stress change tests especially in connection with mircomechanisms. Thanks

Hey all, I'm been working on creep in metals for a while. Could anyone please suggest experiments I can use to show the balance of recovery and strain-hardening in creep. Any guidance would be pretty helpful.

Hello, I'm writing a paper on the effect oxidation has on creep in metals. I'm a bit lost as I've been able to find is papers on this topic for specific metals. Could anyone suggest a good paper or good book that could help light the way that talks on diffusion creep or better still the...

What is the difference between dynamic creep and fatigue? How are they tested?

Do anyone here can thorugh some light on the creep prroperty of Rene-41. I want to know how this material behaves @1400F? Thanks in Advance Sid...

Hepl needed, Can anybody help me to explain creep in polyoxymethylene, its urgent!

Ok, I need some help settling another piano tuner argument. When a piano string breaks and is replaced with a new one, it takes many tunings until it becomes stable. It can be brought to the correct pitch, and will seem to stay there, but in a few days it has dropped in pitch drastically...

Hi, I'm new here, and I'm not really sure where this thread goes, so please feel free to move it Homework Statement basically, I'm doing a project involving converting raw data on pressure and temperature (and time) in a power plant situation (mainly the pipes carrying the steam) here is...

Wire "Creeping" Thin wires tend to creep (extend longer over periods of time), particulary at high temperatures. Is there a "formula" that explains this correlation of the amount of creeping with regards to temperature or other factors?

I had never heard the expression before but what a great way to say it! Most of my work is tied to R&D, which makes scope creep a common problem for me. We start a project with goals A-F, but over the course of several months or more the customer begins to understand more clearly what is...

What is the difference between these two phenomena? Or are they the same thing? I have heard both terms used in different classes, but they seem to be the same or similar.