Composite Specimen Testing

[yusf]

Hi all;

Nowadays i am searching the composite material coupn testing and extracting datas for finite element analysis..

For that purpose i am reading ASTM standarts and ENXXXX standarts in which all says taht the specimen t be tested should be in some thickness with certain number of layers..

BUT what i would like to know is that i model the composite materials ply by ply and i enter the layer mechanical properties to perform finite element calculations rather than the mech prop's of the specimen tested.

How can we extract the layer mechanical properties from the coupn testing which has some layers.In other words the individual layer properties?

All data or guidence will be appreciated.

Thanks in advance..

 

[SWComposites]

What properties are you looking for? stiffness? strength?

Is your material tape or fabric?

If you need tape stiffness properties, typically tests are run on unidirectional [0] and [90] layup specimens for 1 and 2 direction stiffnesses, and on +/-45 layup specimens for 12 shear modulus.

 

[yusf]

Hi;

Thank you for you reply..

Well since i am trying to carry out the finite element analsis for my design in Abaqus environment i need to enter the
E11 E22 G12 v12 etc and also in order to request Tsai-Wu index for example i need also enter the strenght values for the lamina ( ply )which has 0.2 mm thickness in abaqus. ( i think i should enter the mechanical properties for this 0.2 mm thick lamina am i right?)

BUT if i conduct a coupon test according to ASTM or EN XXXX standarts i have to conduct some test to find allowables for let say 3 mm thick coupon .. but in my design i have for example 2 mm 4 mm 9 mm thick regions .now in order to get Tsai Wu index which mechanical properties should i use for lamina or 3 mm standart specimen properties? dont i need to have individual lamina or ply strength and stiffness parameters? how can i extract them or what is the procedure? or do i need to extract them from test specimen result by applying classical lamina theory by back calculations ( from laminate to lamina)?

I hope i am clear .. Any comment will be appreciated...Thanks.

 

[cloa]

Tsa Wu Index is nearly impossible for Orthotropic materials (Biaxial stress tests are needed) ignoring the aspect that its not really representative of how composite really fail.

 

[yusf]

Hi recently i read papers about extracting lamina mechanical properties needed for FEA.

I wonder if anyone gives me information about the process of performing finite element analysis of composite after conducting the laminate coupon tests according to ASTM standarts?

How do we manage the test datas as input of material properties?

i need guidence