Hello All Researchers,

I'd like to know your opinion about some key points that make a research statement so effective. There are so many information, tips and advices in the internet. But, I am looking for your personal experiecne to write simple, quick and effective research staement. I would appreciate if all of you share with me some your tips.

 Best Luck,

Hadi 

 Dear all,

I am doing a fracture analysis of composite beam using ANSYS please let me know about the type of elemnt that i should use for meshing?

thanks in advance 

Dear all Researchers, 

 I am writing regarding for the first time about the UAA(Unified analytical aspect) on Fatigue crack growth. The idea of this technique is this question : too many fatigue life prediction relations but still those are not perfect. on the other hand, new math ways still have not been the classical fracture mechanics. I am looking for some comments as response to this concern. Clearly, how we upgrade fracture mechanics theory using atomistic development in modeling fatigue propagation?

 Let us talk about this.

Regards,

Hadi 

Hi everybody

 I want to ask you regarding the general pattern of diagram da/dn Vs. DeltaK(stress intensity factor) for Variable amplitude loading? Could we share our knowleadge in this case?

Regards,

Hello, my question meaning that developed crack closure model can be explained the damage interaction among cycles of loads, is it right that each cycle has a own damage how can interpolate the overall dame in realistic as possible? which model do you suggested that can be contribute in this issue consider crack closure model?

Hello everyone,

I am looking for a way to measure notch tip radius experimentally. Would you give me some ideas about that? is there any relationship between  morphology of notched cracked body surface and notch tip radius?

 Thank you and Regards, 

there are two analytical concepts that are very important in fatigue failure.the first one is crack closure and the others is residual stress .the first one is in behind of crack and the other emphasis in the front of crack tip. the question is if we use some devices such as AFM/SEM is it possible we model the energy filed during fatigue process?   if this idea can be investigated the second question can be asked: is there any similarity to model for different loading conditions? 

I appreciate if you also put your comment in my idea?

Bes Regards,

Hadi 

Hello everyone,

I would like to read more about piezo ferroelectric materials  i appreciate if give me some idea regarding application and challengable issues in this subject.

Thank you

thank you for comments. Could you clarify to me what do you mean from generation force? as I know there is no generation force. in fact i think this is a energy transformation. 

hello everyone

A question how is possible in the same material and in the same temprature we observe some different material properties? as we can see in shape alloy effect? I appreciate if somebody give me some clues as a light to shed the research way. thank you in advance.

Hello everyone,

I intend to model liquid material using ABAQUS but i do not know how put the values and define the specific material. I appreciate if guide me.

Thank you 

Hello Everyone,

What was the observations of crack closure by Elber? I appreciate if everybody address me to extra info about that. the significance in that they were attempts to clarify Fatigue crack growth behavior.

Thank you. 

Hello all Prof,Researchers and students

 more than 150 person have read the question but until now I have  no feedback. I really appreciate if what you think in your head share with me even if you think it is not so comprehensive. 

Bes Regards,

Idah 

Hello Everyone,

Could you address me to a comprehensive description for relationship between fatigue and fracture  in prediction life Fatigue crack growth life?

i appreciate in advance,

Hi everyone,

As we know obviously Dk in paris equation is an applied value for stress intensity range. we can either measure or calculate it according to fracture mechanics principle depends on geometry, crack length, etc . also we know that this equation can not support VAL conditions. now the question is if we make a change in stress/strain amplitude,besides we use a parameter to accumulate damage such as (Smith W-Topper parameter)to interlink between fatigue and fracture is it possible modify Dk in paris equation in way that corrected value can support Constant amplitude loading block which each block has a constant amplitude?

if you have idea about this i am very eager to hear you and discuss about that.

about 3 day have passed really nobody can do not give some idea about solving this equation?

Hello every one,

Please look at attach file and let me know your idea about solving this nonlinear system equations. 

Hello everybody,

my question regarding how can calculation stress/strain field as well as good agreement with experimental results? espesially in crack tip and the behind of crack trip?

 thank you for your help in advance

Hadi

Hello 

what do think why investigators await about 3 decades to calculation of local stress/strain by elastic-plastic fracture mechanics?and basically why elber's discovery[crack closure] was so important and play a key role in numerous articles?

How can i calcualtion the amount of load transfer through the contacting crack faces?

How can i determine the location of it?

Thank you

Hadi

measurment of FCG based on crack tip closure concept depend on :

1- experimental technique

2-location of the measurement

3- mean stress effect on FG at high stress ratio can not be explained by the closure model due to the absense of the crack closure at high loads.

Two question can be investigated as follows:

1- why crack tip closure is popular and it widely use in hightech industry like aircraft industry acording to overwiew of scentific articles.?

2-basically if we can define clearly residual stress in plasic and cyclic zone mathematically not physically what will happen in developing of crack tip closure concept?

Thank you,

Hadi

Thank you for all of quick response. Yes, I need a calculation method as long as good agreement with measurment methohs.Generalization will be important in which method we choose espesially in calculation of stress field.

It seems that the measurment of local stress and strain in fatigue crack tip will be difficult. some researcher use F.E analysis method,in contrary using of numerical solution. however analytical method also has investigated. what method you can imagine? i need a brain storm in this issue.

Thank you

Hadi