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Mtech thesis doubts

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Frown Want it urgently

Johnson Cook damage criterion for Alloy 718

Hi I'm looking for a Johnson Cook damage criterion for Alloy 718 (or Iconel 718) i.e. the constants (D1,D2,D3,D4,D5).

If anyone seen an article or book with these constants I would be thankful if you could help me out.

Thanks in advance

cohesive zone with curvature


Anyone have experienece of curved cohesive zone model?

I just find people just use straight line cohesive zone geometry model.

Any difference between these two geometries?


cohesive zone model simulation :abaqus standard mode or explicit mode?

Since the available literature related to cohesive zone model simulation is done in abaqus standard mode, I'm curious if it is suitable to simulate in abaqus explicit mode.

Could you give me a suggestion?Thanks.

Composite Damage model

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   Everybody I am trying to design a composite layup and to design a
bulleye hitted by a blunt bullet  and need to do element deletion on it
by using hashin damage model in abaqus but I am new to abaqus please
help me regarding designing of lamina ,failuremodel and element deletion

Starting out question

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This is my first post so bear with me.

I have a question and an answer but have little idea how they got the answer.  The question relates to a sample with load being applied at both ends.


mathematical equation for a crack in a ductile material

hi all,

im an engineering doing a project on crack behaviour in a ductile material(mild steel) when a load is applied on going to analyse it using ANSYS, for validating this i need a mathematical plz if you have mathematical equations and journals regarding it plz reply me ...thank you... 


Literature regarding the appearence of cracks in steel. Thermal, pressure fatigue

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I am wondering if anyone could recomend som literature for me to get my hands on.
If there is any literature regarding how the appereance of a crack in a piece of thin metal (~0,5mm - 1 mm) could be related to pressure fatigue or thermal fatigue.
Does the crack due to thermal fatigue have a specific appereance and so on. I need get my hands on practical pictures and so on, not equations.
Are there any signs in the vicinity of the crack that is indicating that this could be due to pressure fatigue.

Any help is much appreciated.


3D modelling of an ellliptical crack in ANSYS

I am a beginner in FEM and just started using ANSYS.  I need to study the stresses and SIF at the crack front of an elliptical crack inside a material subjected to a stress perpendicular to the crack plane.  Any details on how I should build my model?  

What is the easiest way to define a cracked area, and crack front and then mesh it

How can i merge together a cracked area and an unmeshed area? 

I found a lot of links and articles that states they did it, but none explained the procedure do do it. 



Pooyan's picture

Failure Criteria


I want to know in Ansys software, what are the failure criteria values for steel in picture below?


Failure Criteria 





How to plot J-integral path

Dear all,

I am a new Abaqus user. My work involve with fracture modelling by using Abaqus.

I model 2D-Edge Crack problem by using Abaqus. For the output, I request 5 values of J contour integral at the file history output, and Abaqus provides me 5 values of J - integral. However, I can not plot the J-integral path (J - integral versus Radius). I know abaqus will choose the path of each contour integral automatically. But I don't know how to show the path of each contour integral.

 Could you please suggest me how I should do.  

smilehan001's picture

problem when using chesive element, seeking help

Hi, I use the chesive element to simulate the debonding of particle in matrix.
I edit the mesh to make the thickness of chesive element to be zero. When I submit the job,
error comes:
The geometry of 30 elements is too distorted. Check the nodal coordinates or node
numbering on elements identified in element set ErrElemDistorted.

If I don't make the thickness to be zero, it goes well with ABAQUS 6.10.
Can anyone help me?

How do I determine if J-integral is needed?

Basically I would like to know if I need to use J-integral to analyze a crack. From what I think I know, the stress intensity factor, K, can be used to analyze crack growth if the plastic zone ahead of the crack tip is within an elastic singularity zone. If the plastic zone is large (i.e. plastic zone is not embedded within elastic singularity zone) then J-integral should be used, correct? This singularity zone is where stress is proportional to 1/r^0.5.

Rerun input file with ABAQUS software from a certain time



There was a time i run my input file of 3D model with ABAQUS. It was supposed to take more than one day in order to complete analysis. But unfortunately my computer was turned off, then i had to rerun input file from beginning even running process was completed almost 85%. Is there anyone knows the way to rerun input file from the time it was ruptured? 


Tuan Son

Fatigue life calculation of a component in multi-axial stress state

I am dealing with a high cycle fatigue life calculation of a component which is under a constant amplitude proportional loading, however this component is in multi-axial stress state. In fatigue life calculation we deal with uniaxial stress. Now which uniaxial stress measure (equivalent, maximum principal, minimum principal or absolute maximum of maximum and minimum principal stress) should be used in fatigue life calculations?

fatigue crack growth curve

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I implement a program for fatigue crack growth in the XFEM.

But I have great difficulties to find material parameters used for PARIS- or  FORMAN/METTU-equation.

Can anyone point me where this parameters could be released, for example for epoxy, polyurethane, 18CrNiMo7-6 and Aluminium.

I would very appriciate your response.


Damage Modelling in XFEM

I am currently attempting to model a crack simulation using realistic values for materials such as aluminium and cast iron. I was wondering if anyone knew of a resource which might provide standard values for MAXPE/MAXPS in the damage initation command and for the parameters in the damage evolution command.

Any help would be much appreciated.




[SOLVED] 3D crack growth modelling in Abaqus by XFEM

Good day everyone,

I'm new to iMechanica and look forward to getting to know everyone here. Smile

I'm currently doing analysis of interlaminar crack growth in fibre-reinforced composite by Extended Finite Element Method (XFEM) using Abaqus. I'm a new Abaqus user and therefore I have to familiarise myself by constructing random 2D and 3D models with isotropic materials before jumping onto anisotropic.

Experimental data with different specimen sizes for single notch bending test

Experimental data with different specimen sizes for single notch bending test

Hello, everyone 

Haroon's picture

crack progagation whith XEFM

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hi all im using abaqus 6.9 to simulate a crack propagation in an elastic material whith Xfem option, i still have this errors :the following XEFM crack are failling to correctly generate the conditions are listed whith the crack names : crack-1 Failed to locate crack tip.
 and if i submit the job even the warning its abort and i get this error:the damage model has to be specified for enriched element ( nbre) instance part 1-1.i specify the damage  model in Intprop as follow
*Material, name=Material-1
 2.1e+11, 0.3

numerical modelling of orthogonal machining

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hello guys,

             i am trying to model  machining process especially i am trying to simulate varation of chipreduction coefficient wth uncut chip thickness so can any one send papers regarding this 

so plz help me

Ductile fracture prediction in Taylor Test

I am reading the Weirzbicki's paper titled "Numerical Prediction of fracture in the Taylor test". I do not understand the terms stress triaxility and Lode angle parameter clearly. What does the term "negative stress triaxiality at -1/3" stand for? Kindly explain me these two aspects clearly and also provide some references for reading.

Thanks and Regards,

Siva Prasad A V S.

rajnish0007's picture

How to simulate pull out test in ABAQUS ??

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hello all

How to simulate pull out test in ABAQUS 6.9  ???


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