Functionally Graded Materials

There are many groups working on FGM and applications.  Recently from my study we foudn that the FGM can be used in devices with distinct properties.  There are tremendous literatures on FGM and it is relatively easy to trace the new directions of such groups.

Ji Wang

Hi,

i am also working in the area of FGM. Let me know if we can share the knowledge.

sandy

  Is optimization of Material Profile for funtionally graded material to reach    maximum Transmission loss or maximum critical frequency coud be interesting topic?

Dear Roozbeh,

 Can u tell us in details?

Sandyg 

Functionally graded materials are investigated in literatures in two cases:

1- Mechanical behaviour under thermal conditions

2- Mechanical behaviour without considering the thermal loading (Free vibration, dynamic response, static response...)

I want to know if thermal loading can be seperated from FGM analysis and studying FGM structures without thermal loading is applicable?

And also I want to know which method is more usefull in dynamic analysis of functionally graded structures?

Ahmad Rafsanjani Abbasi

each funtionally graded material have material profile that shows how material distributes over the material. this profile could be optimized in order to reach a purpose. i want to optimize it in order to reach maximum transmission loss or critical frequency.

is it an interesting objective?

Hi all,

nice to see all of u here. I am working on the mechanical properties of FGM and material is epoxy resin and Microballoons. we are into fabrication and testing of these materials. I finished one project recently and that was flexural testing of FGM. I do understand a little bit what Roobeh is saying but probably need more reference on these kind of works. Is there any good journal paper? I would suggest to start with some problem and discuss on that so that we can learn some good stuff here. so if everyone thinks its a good idea then post one problem. 

Sandy 

I think the advantages of FGM materials is behined its response due to thermal loading. in many cases however many researches performed their researches on FGM materials without considering thermal condition of the problem but in most cases it is obviuos that using functionally graded materials will not only improve mechanical properties of the structure but also makes it worse (if there is not thermal loading). I think the aim of design of FGMs is to be capable to prevent stress concentarion and some sharp behaviour in the systems. unfortunately in many cases the papers published in this field are far from reality and are not applicable in industrial scales. thanks to Mr Kubair for sending these usefull references.

If you have any other opinion about this topic, o not hesitate. let me know.

Best regards,

Ahmad Rafsanjani Abbasi

I think the advantages of FGM materials is behined its response due to thermal loading. in many cases however many researches performed their researches on FGM materials without considering thermal condition of the problem but in most cases it is obviuos that using functionally graded materials will not only improve mechanical properties of the structure but also makes it worse (if there is not thermal loading). I think the aim of design of FGMs is to be capable to prevent stress concentarion and some sharp behaviour in the systems. unfortunately in many cases the papers published in this field are far from reality and are not applicable in industrial scales. thanks to Mr Kubair for sending these usefull references.

If you have any other opinion about this topic, o not hesitate. let me know.

Best regards,

Ahmad Rafsanjani Abbasi

Kubair,To answer your question on how to measure the mechanical properties like elastic modulus and poisson’s ratio, you can use the ultrasonic probe which gives the shear and longitudinal velocities which then can be used to calculate modulus and poisson ratio.I hope I understood your question correctly.  Thanksnitesh

nitesh

Different types of armor are used to protect different areas of the vehicle, partly to reduce weight for a given amount of protection and partly to combine projectile protection with load-bearing capability. These protection system components will consist of combinations of metals, ceramics, and polymers.

Functionally graded metal/ceramic composite materials can combine the beneficial properties of a metal toughness, ductility, heat conductivity with those of a ceramic hardness, stiffness, heat resistance. The ceramic side would be brought into contact with the external agent and the metal side would provide integral structural support.

I am glad to see there are overwhelm interests in the FGM and applications.  We have been working on FGM for about two years with sponsored projects.  Major research work are being done by Prof Zheng Zhong, Tongji University, Prof Weiqiu Chen, Zhejiang University, with a number of collaborators in other schools.

The basic approach has been usual: particular pattern of FGM which can give you analytical solutions first, then extended to other schemes.

For myself, I am intersted in FGM in acoustic wave devices, which may lead to new device structures.  We have some results and publications, and more results are in the pipeline.

What we have found is also usual: the differential equations fromthe complicated material property change can be solved by Forbenius Method.  Lately, we are tryign to use the HAM (http://numericaltank.sjtu.edu.cn/) for the equations to be solved.

For books, one by GR Liu, CRC Press, maybe closer to the analysis and FEM part.

It is always great to meet colleagues on the same subject.

Hi,

i'm interested in numerical analysis of fgm. but i need apdl codes for describe material properties of fgm.

Can you help me?

Thanks.

Ulukoy,

we carried out some numerical simulations of deformation and damage behavior of Functionally graded Composites. In so doing, we considered first a particle reinforced composites with graded particle distribution and non-percolating microstructures, and then graded interpenetrating phase composites. You can download papers from http://www.risoe.dk/afm/personal/lemi/, in particular, http://www.risoe.dk/afm/personal/lemi/papers/voxel-paper.pdf and http://www.risoe.dk/afm/personal/lemi/papers/paper_fgm.pdf.

Best Regards

Leon Mishnaevsky, Denmark

Dear Mishnaevsky,

Thanks for the papers. I will examine power law fgm first,  and then

sigmoid and exponential fgm.

Best Regards

Hi all,

I want to know which factories product FGM.

Thanks.

hi,

our group is studying 3D cracks problem in fully coupled electromagnetothermoelastic multiphase composites about 8 years.

perhaps i think we can solve shell crack problem byhypersingular integral equation method

if you interested this method you can find related papers on web: Noda, N.A; Taiyan Qin; Renji Tang; Mengcheng Chen; Chaojin Yue; Chunhui Xu; Pan ernian et al

Hi,

In the theoritical/computational analysis, one or more propertis are assumed to vary according to some function. I was interested to know (mainly from manufacturing/experimental groups), what are the properties that may be varied or if they may be varied according to any mathematical function or not. It will be helpful to get some works regarding this.

Sandip Haldar

i would like to have some assistance from all regarding crack propagation in annular disk at tang location using ABAQUS

Hi,

i am working on fracture in FGM shell element applying cohesive zone model. So, i am including the rotation effect in the Xu and Needleman´s potential  and using 3D interface line element. I´d like to know if there are someone doing something similar.

Thanks for all

Nice to see all of you here. I am working on the mechanical properties of FGMs. I want to know recently model for FGMs plate. Multi-layered based on Mindlin theory can be applied? Plz help me to know that.

Thks

I' m also involved in the field fo FGM, but my concern is more practical application. I'm investigation contact stress and fretting wear of ball-track contact  of a ball bearing like part, the case or inductive hardened surface of the track is typically plastically graded material,  when the surface is coated, then, which becomes a problem of elastic graded material. My concern is to anlysis the fracture and fatigue considering this kind of graded surface(first, only pay attention to plastically  graded surface) . But, the problem is how to reflect this kind of graded surface in FEM model(I use ANSYS) in contact analysis?

I' m so glad there are so many experts here, and please share some experience of FEM anlysis of DGM, or kindly give me some advices.

Hello, dear Kubair

     Recently, I'm thinking about this problem:common engineering processes such as shot peening, ion implantation, deep rolling and case hardening introduce graded surface to machine elements in a controlled manner, especially hardening case or induction hardening are often used to modify the surfaces of many machine element, such as bearings and gears. 

   My question is: will this kind of (most of time is plastically) graded surface affect the fracture or failure of the contact surface? In another words, different engineering processes(such as case hardening and induction hardening) introduce different plastically graded surface, will this affect the failure of the contact surface?

   Can you kindly give me some advice?

Dear Professor Kubair:

    Your answer to my doubts really inspired me! Thank you very much!

In your comments saying"The length scale of the property gradient might not be comparable to the size of the plastic zone.Fatigue, fretting and fracture of plastically graded surfaces could be different depending on the inhomogeneity length scale. "

 Is it means that it is not worth to pay attention to this kind of plastically graded surface?

and, about the "fretting and fracture of plastically graded surfaces could be different depending on the inhomogeneity length scale", can yur kindly suggest me some literatures or bookd to get more information about this problem.

 Sincerely yours

  Longjiang

Dear Professor Kubair:

    I've read your paper, it is obviously that you and your group have done very much significant work in this field! but I have a further question:

   1.In your paper:"The plastic material gradient is assumed to be in the radial direction only", in what kind of engneering will occur similar situation?

2. In normal engineering surface, the drection of the plastic gradient is from the surface to the  core(most of the time the yield strength is deacrease from the surface to the core), when the plastic gradient is big enough, can it prevent the crack beneath the surface develop towards the surface?

your sincerely

Longjiang

Dear Professor Kubair:

About using multiple isoparametric finite elements to model graded materials, can you give me move details? I can only find isoparametric element in ANSYS but not multiple isoparametric elements. And can you  give me a example of modeling graded material using a certain standard finite elements software?

thank you very munch!

your sincerely

HI  everybody

as well as mr. Venkat Bharath i am working on buckling of fgm cylindrical shell in the thermal inviorment.

IS it possible to create a FGM material bevavious in Abaqus??

am currently doing my project in functionally gradient materials..i
want to know the journal papers/notes regarding functionally gradient
bronze alloys 1)how to prepare functionally gradient materials 2)what
are the properties we can achieve.3)

hi, everyone i want to model fgm in ansys ,can anybody help me?

PRADEEP KUMAR J

Hi

a want to model a FGM timoshenko's beam in abaqus. i don't know how simulate a fgm in abaqus. just there are two ways for modeling. the first way is UMAT and second way is partitioning. i'm interested to know a bout modeling with partitioning. i don't know about this. plz help me. if any one have toturial file about modeling, i think it is very useful for me.

thanks