Author
Guo-Ji Li
Bio: Guo-Ji Li is an academic researcher from University of California, Berkeley. The author has contributed to research in topics: Plane stress & Finite element method. The author has an hindex of 1, co-authored 2 publications receiving 172 citations.
Papers
More filters
178 citations
Cited by
More filters
25 May 2005-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: Steady-state friction stir welding of stainless steel has been modeled using an Eulerian formulation that considers coupled viscoplastic flow and heat transfer in the vicinity of the tool pin this article.
Abstract: Steady-state friction stir welding of stainless steel has been modeled using an Eulerian formulation that considers coupled viscoplastic flow and heat transfer in the vicinity of the tool pin. Strain hardening is incorporated with a scalar state variable that evolves with deformation as material moves along streamlines of the flow field. The model equations are solved using the finite element method to determine the velocity field and temperature distribution, with a modified Petrov–Galerkin employed to stabilize the temperature distribution. The evolution equation for the state variable for strength is integrated along streamlines using an adaptive procedures to determine step size based on the element size. The intense shearing and associated heating lead to complex behavior near the tool pin. The effect of this complex response is demonstrated with the crystallographic texture, which displays a nonmonotonic strengthening and weakening history along streamlines that pass close to the tool pin.
195 citations
TL;DR: In this article, a hot rolling process of AA5083 aluminum alloy is simulated using the finite element method, where the temperature distribution in the roll and the slab, the stress, strain and strain rate fields, are extracted throughout a steady-state analysis of the process.
113 citations
TL;DR: In this paper, the Coulomb friction law and the constant shear friction law were compared and investigated in detail using a rigid-plastic finite element method with emphasis on their application in bulk metal forming.
113 citations
TL;DR: In this article, a review of the models used for the mechanical study of cold strip rolling is presented, focusing on steady state formulations for lower cost, on roll and stand deformation to study the essential problems of profile and flatness defects.
104 citations
TL;DR: In this paper, a method for simulating three-dimensional steady-state deformation in shape rolling with grooved rolls by the rigid-plastic finite element method is proposed, where contact of the nodal points with the roll surface and detachment from the surface are judged in each step of calculation.
Abstract: A method for simulating three-dimensional steady-state deformation in shape rolling with grooved rolls by the rigid-plastic finite element method is proposed. For the three-dimensional element mesh, contact of the nodal points with the roll surface and detachment from the surface are judged in each step of calculation. The boundary conditions of metal flow along the curved roll surface and of friction between the roll and the workpiece are dealt with at each node over the interface. Complex steady-state deformation in shape rolling is simulated by using the non-steady-state scheme and the remeshing technique. As examples of simulation, rolling processes of bars and beams with grooved rolls are chosen. The deforming shape, the rolling torque, the roll separating force and the distributions of stress and strain in the workpiece are computed.
71 citations