Abstract
A method to incorporate grain size effects into crystal plasticity is presented. The classical Hall-Petch equation inaccurately predicts the macroscopic yield strength for materials with non-equiaxed grains or materials that contain unequal grain size distributions. These deficiencies can be overcome by incorporating both grain size and orientation characteristics into crystal plasticity theory. Homogenization relationships based on a viscoplastic Taylor-like approach are introduced along with a new function, the grain size and orientation distribution function (GSODF). Estimates of the GSODF for high purity α-titanium are recovered through orientation imaging microscopy coupled with the chord length distribution. A comparison between the new method and the traditional viscoplastic Taylor approach is made by evaluating yield surface plots.
Degree
MS
College and Department
Ira A. Fulton College of Engineering and Technology; Mechanical Engineering
Rights
http://lib.byu.edu/about/copyright/
BYU ScholarsArchive Citation
Fromm, Bradley S., "Incorporating Grain Size Effects in Taylor Crystal Plasticity" (2007). Theses and Dissertations. 1275.
https://scholarsarchive.byu.edu/etd/1275
Date Submitted
2007-12-21
Document Type
Thesis
Handle
http://hdl.lib.byu.edu/1877/etd2261
Keywords
texture, strength, grain size, viscoplasticity, yield surface, titanium
Language
English