Investigating Fracture Behaviors of Polymer and Polymeric Composite Materials Using Spiral Notch Torsion Test
- ORNL
- Montana State University
- Gougeon Brothers, Inc.
- Molded Fiber Glass Companies
Wind turbine blades are usually fabricated from fiber reinforced polymeric (FRP) materials, which are subject to complex loading conditions during service. The reliability of the blades thus depends on the mechanical behaviors of the FRP under various loading conditions. Specifically, the fracture behavior of FRP is of great importance to both the scientific research community and the wind industry. In the current project, a new testing technique is proposed based on the spiral notch torsion test (SNTT) to study the fracture behavior of composite structures under mixed mode loading conditions, particularly under combined Mode I (flexural or normal tensile stress) and Mode III (torsional shear stress) loading. For the SNTT test method, round-rod specimens with V-grooved spiral lines are subjected to pure torsion. Depending on the pitch angle of the spiral lines, pure Mode I, pure Mode III, or mixed Mode I/Mode III loading conditions can be simulated. A three dimensional finite element analysis is then used to evaluate the fracture toughness and energy release rate of SNTT specimens. In the current study, both epoxy and fiberglass reinforced epoxy materials are investigated using the SNTT technique. This paper will discuss the fracture behaviors of mode I and mixed mode samples, with or without fatigue precrack. In addition, results from fractographic study and finite element analysis will be presented and discussed in detail.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 1040742
- Journal Information:
- Engineering Fracture Mechanics, Journal Name: Engineering Fracture Mechanics; ISSN 0013-7944
- Country of Publication:
- United States
- Language:
- English
Similar Records
Fractographic study of epoxy fractured under mode I loading and mixed mode I/III loading
Fracture Toughness Evaluation for Spent Nuclear Fuel Clad Systems Using Spiral Notch Torsion Fracture Toughness Test