Affiliation:
1. Materials Forming, Department of Production Engineering, Royal Institute of Technology, 100 44 Stockholm, Sweden
Abstract
The influence of material anisotropy and friction on ring deformation has been examined in relation to the distribution of normal pressure and frictional shear stress, deformed ring shapes, and estimated errors in the coefficient of friction. Based on the flow rule associated with von Mises’ and Hill’s yield criteria, the analyses have been carried out with the finite element method (FEM) for three cases, namely, (1) an anisotropic ring oriented 90 deg to the axis of rotational symmetrical anisotropy under uniform coefficient of friction; (2) an isotropic ring under frictional anisotropy condition; and (3) an anisotropic ring oriented 0 deg to the axis of rotational symmetrical anisotropy under uniform coefficient of friction. In the first two cases, the results show that the influence of anisotropy on ring deformation is quite similar to that obtained by changing the frictional condition. Therefore, in the third case, if the anisotropic behavior is mistakenly attributed to friction, the possible estimated error for the coefficient of friction can be as high as 80 percent for a pronounced anisotropic material. Deformed ring shapes have been verified in experiments using the extruded annealed aluminum alloy AA6082 (Al-Si1Mg0.9Mn0.1).
Subject
Surfaces, Coatings and Films,Surfaces and Interfaces,Mechanical Engineering,Mechanics of Materials
Reference17 articles.
1. Kunogi, M.
, 1956, “A New Method of Cold Extrusion,” Journal of the Scientific Research Institute, 50, pp. 215–246.
2. Male, A. T. et al., 1964, “Coefficient of Friction Under Condition of Bulk Plastic Deformation,” J. Inst. Met., 93, pp. 38–46.
3. Garmong, G. et al., 1977, “An Evaluation of the Ring Test for Strain-Rate-Sensitive Materials,” Metall. Trans. A, 8A, pp. 2026–2027.
4. Danckert, J.
, 1988, “Analysis of the Ring Test Method for the Evaluation of Frictional Stresses in Bulk Metal Forming Processes,” Annals of the CIRP, 37(1), pp. 217–220.
5. Tan, X., Martin, P. A. F., Bay, N., and Zhang, W., 1998, “Friction Studies at Different Normal Pressures With Alternative Ring-Compression Tests,” J. Mater. Process. Technol., 80–81, pp. 292–297.
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