Files in this item
|(no description provided)|
|Title:||Predictions of Monotonic Tensile Stress-Strain Curves of Short Fiber Reinforced Polymer Composites|
|Department / Program:||Mechanical Engineering|
|Degree Granting Institution:||University of Illinois at Urbana-Champaign|
|Subject(s):||Engineering, Materials Science|
|Abstract:||A method for predicting the non-linear monotonic tensile stress-strain curves of short fiber reinforced polymer composites with different fiber orientation distributions is developed.
Three-dimensional finite element models are used to analyze microcracking effects the elastic constants of an aligned short fiber composite. Two damage state variables are defined. One represents the total area of parallel cracks (cracks run parallel to fibers) per unit volume, the other one represents the total area of perpendicular cracks (cracks run perpendicular to fibers) per unit volume. These two variables are used to relate the applied strains to the degraded elastic constants of an aligned short fiber composite. Once the microcracking effect on the properties of an aligned short fiber composite is known, the average microcracking effect on the properties of short fiber composites with different fiber orientation distributions can be evaluated by orientation averaging.
A prediction procedure which considers the effect of the microcracks is developed to predict the monotonic tensile stress-strain curves of short fiber composites with different fiber orientation distributions. Comparisons of the predictions and the experimental results show that the theoretical models predict the monotonic tensile stress-strain curves very well. The models not only predict the anisotropic properties of the material but also capture the feature of nonlinearity. The worst error in predictions is less than 7 percent.
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1984.
|Date Available in IDEALS:||2014-12-15|
This item appears in the following Collection(s)
Dissertations and Theses - Mechanical Science and Engineering
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois