No Shear plasticity data input option in abaqus

[abc123ali]

Respected ABAQUS users, There is no option avaiable to input shear plasticity data in abaqus but just an option of shear damage which is what not reqired. I need to check the shear yielding of the binder applied between the diamond plates. Here as far as experimental facitlity is concerned its easy to perform shear experiment and get data compare to tension test. So how can I utilize my shear data to perform fem analysis in ABAQUS?
Thanks

 

[FEA way]

Basically, you have the following options:
- perform a tensile test of the adhesive material to get the data needed for regular plasticity definition (not only Abaqus needs that, all FEA software uses the same approach)
- estimate the tensile data (yield strength/UTS) from shear data - easy for metals, tricky for other materials
- use a different material model for the adhesive - the choice depends on the type of adhesive but shear test data may not be sufficient anyway
- model the adhesive differently - using the common CZM approach
- simulate the shear test, assume some tensile plasticity data and try to calibrate the model this way (iterate until the results are in good agreement with experimental ones)

There's an interesting white paper "Introduction to Modeling Structural Adhesives" by 3M that you can find online.

 

[abc123ali]

Resepecetd FEA WAY,

How can I estimate the tensile data (yield strength/UTS) from shear data - easy for metals, tricky for other materials? My material is mixture of metal nanopaste mixed with some organic binder for joining which when cures at certain temperature becomes partially brittle and partially elastic material; the values of yield and UTS is unknown due to experimental complexity because the plates are very thin and the binder layer thickness is just 100 micron, but I think I can consider it as elasto-plastic binded joint? Suggest me better way.

How can I simulate the shear test as there is no input option of shear plasticity data in ABAQUS ? How can I assume some tensile plasticity data and try to calibrate the model this way iterate until the results are in good agreement with experimental ones?

What should be third variable other than shear stress-strain, tensile stress-strain which will be very suitable to iterate or if I try to use shear data and perform tension test by apply loads in tension mode get some data and than reuse this data and perform shear test from this data to get the values closer to satisfy shear data by reapting the procedure. So what should the iteration procedure be like?

Thanks

 

[FEA way]

I doubt you can estimate the tensile properties of such a material from shear data with sufficient accuracy so this approach might be inapplicable here. If you can't perform a tensile test, I would suggest modeling the adhesive using cohesive elements or surfaces. This also requires some inputs but it might be easier to get them from your data.

The last approach that I described is the "least professional" one. Theoretically, you could enter some approximately reasonable tensile properties (e.g. from research papers discussing similar materials or somehow derived from your test data), model the experiment that was performed to obtain the data you have and plot the resulting shear stress vs strain. It won't match the data you have initially so try adjusting the tensile data that you used and running again. Repeat until the outputs are in good agreement with the experiment and then you will have your adjusted tensile data for use in other simulations. But again, this is the last resort.