Doctoral Dissertations
Abstract
"Radial forging is an important manufacturing process to produce large cannon barrels. It is used to improve the material properties and reduce the porosity of the billet. The objective of this study is to develop finite element models to investigate the behavior of the workpiece and predict the elimination of void defects in the radial forging process. A nonlinear coupled finite element model has been developed to study the behavior of a large-diameter tube subjected to mechanical and thermal loadings in hot radial forging. The model is formulated in a three-dimensional frame, accounting for both axial and circumferential effects. A rate-dependent material model is used to describe the viscoplastic behavior of a workpiece subject to high temperature and large strain. The simulation results are compared with previously published experimental and two dimensional axi-symmetric simulation results. This work also develops a comprehensive three-dimensional model to predict the degree to which void defects are eliminated in the cold rolling process. It compares experimental results to the finite element predictions to validate the model. The void reduction predictions of the finite element analysis agree closely with the experimental findings. Neural network has been used to establish the relationship between the process parameters and the void reduction. Finally the previous model has been extended to examine the mechanism of void deformation subjected to large deformation in hot radial forging. It investigates systematically the effects of void location, mandrel, die shape, and reduction in tube thickness on the final void reduction. The model is verified by comparison with experimental findings. All the simulation results provide a valuable procedure for the design of the hot radial forging process"--Abstract, page iv.
Advisor(s)
Chandrashekhara, K.
Committee Member(s)
Dharani, Lokeswarappa R.
Du, Xiaoping
Tsai, Hai-Lung
Richards, Von
Department(s)
Mechanical and Aerospace Engineering
Degree Name
Ph. D. in Mechanical Engineering
Sponsor(s)
Benét Laboratories
Missouri University of Science and Technology. Department of Mechanical and Aerospace Engineering
Publisher
Missouri University of Science and Technology
Publication Date
2011
Journal article titles appearing in thesis/dissertation
- Three-dimensional nonlinear finite element analysis of hot radial forging process for large diameter tubes/li>
- Void closure prediction in cold rolling using finite element analysis and neural network
- Study of void closure in rot radial forging process using 3D nonlinear finite element analysis
Pagination
xi, 135 pages
Note about bibliography
Includes bibliographical references.
Rights
© 2011 Jian Chen, All rights reserved.
Document Type
Dissertation - Open Access
File Type
text
Language
English
Subject Headings
Forging machinery -- Mathematical modelsFounding -- Defects -- Mathematical modelsNonlinear mechanicsFinite element method
Thesis Number
T 10162
Print OCLC #
861227583
Electronic OCLC #
908636695
Recommended Citation
Chen, Jian, "Nonlinear modeling and simulation of radial forging process" (2011). Doctoral Dissertations. 2224.
https://scholarsmine.mst.edu/doctoral_dissertations/2224