Ultimate strength prediction of notched and unnotched composites using micromechanics approach
Finite element simulations of three laminates in open-hole and unnotched configurations subjected to tension and compression quasi-static loading are investigated as part of the Damage Tolerant Design Principles program organized by the Air Force Research Laboratory. The coupons are made from unidir
2025-06-28 16:36:29 - Adil Khan
Ultimate strength prediction of notched and unnotched composites using micromechanics approach
Project Area of Specialization Mechanical EngineeringProject SummaryFinite element simulations of three laminates in open-hole and unnotched configurations subjected to tension and compression quasi-static loading are investigated as part of the Damage Tolerant Design Principles program organized by the Air Force Research Laboratory. The coupons are made from unidirectional IM7/977-3 plies, which are a composite material composed of intermediate modulus carbon fibers and a toughened epoxy matrix. Blind simulations of coupon stiffness, nominal coupon stress at failure and damage evolution are benchmarked against experimental measurements and X-rays. The blind simulations are followed by the second round of simulations where the modeling strategy is modified to improve agreement between the simulations and experiments. In the present article, the commercial software ABAQUS is used to model the non-linear response of the composite material along with micromechanics model programming in FORTRAN language. Using Micromechanics criteria, failure is evaluated at the constituent level by extracting the fiber and matrix volume average stress state from the homogenized composite stress state. The relationships between the composite and constituents are developed using the micromechanics theory. The experiments were also performed to validate the micromechanics model.
Project ObjectivesThe objectives are the following:
1. To predict the ultimate strength of notched and Unnotched composites using micromechanics based progressive damage model – Micromechanics Failure (MMF)
2. To validate MMF with experimental results.
3. To compare MMF with other available failure models available in the literature.
4. To predict and compare the ultimate strengths of thick and thin composite laminate using MMF.
5. To predict and compare the ultimate strengths of thermoset and thermoplastic-based composite laminate using MMF.
Project Implementation Method1. Experimental Work
1. Manufacturing of composite panel along with the preparation of the specimen
2. Determination of material and strength properties
2. Simulation Work
1. Determination of numerical model in FORTRAN
2. Development of FE model in ABAQUS
3. Validation of MMF using experimental results
4. Comparison of Thick and Thin composites using MMF
Comparison of Thermoset and Thermoplastic composites using MMF
Benefits of the ProjectProgressive damage model in FORTRAN language to predict the ultimate tensile strength of notched and unnotched composite materials will be developed to save the experimental cost and material losses.
Technical Details of Final DeliverableProgressive damage model in FORTRAN language to predict the ultimate tensile strength of notched and unnotched composite materials.
Final Deliverable of the Project HW/SW integrated systemCore Industry ManufacturingOther Industries Others Core Technology OthersOther Technologies OthersSustainable Development Goals Industry, Innovation and InfrastructureRequired Resources| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 55000 | |||
| Carbon Composite Material along with epoxy | Equipment | 20 | 1500 | 30000 |
| Experiments of Universal Testing Machine | Equipment | 30 | 500 | 15000 |
| NIL | Equipment | 0 | 15000 | 0 |
| Printing etc | Miscellaneous | 1 | 10000 | 10000 |