The Enlargement of a Hole in a Rigid-Workhardening Disk of Non-Uniform Initial Thickness

摘要

A complete solution is obtained for the enlargement of a circular hole in a disk using an isotropic strain-hardening law with Mises' yield condition and its associated flow rule. The results are then compared with those obtained using: (1) Tresca's yield condition and its associated flow rule; (2) Mises' yield condition for the neutral plastic region, and Tresca's yield condition and the flow rule associated with the Mises yield criterion for the active plastic region; and (3) Tresca's yield condition for all plastic regions and the Saint Venant-Levy-Mises flow rule. An interesting feature of the results is that, when material hardening exists and when the Saint Venant-Levy-Mises flow rule is used, then, as the hole expands, there first occurs a thickening of the disk at the vicinity of the hole's edge, which thickening may then be followed by a thinning. It appears that this phenomenon has not been noticed before. (Author)