| A numerical model to simulate the deformations in gear teeth subjected to rolling loads as in the ausrolling process has been developed. Ausrolling involves applying rolling loads to the gear when it is in the metastable austenitic state. A model of the process must consider material, geometric and surface non-linearities as well as changes in temperature and material properties with time and rolling loads in three dimensions. Of these, the elastic-plastic flow; geometric non-linearities due to large deformations; frictional contact conditions at the die-workpiece interface; and the travelling loads due to rolling, have been considered here to be of primary importance. The objective of this thesis is, accordingly, to satisfactorily establish the forementioned features in the non-linear finite element analysis program (NOFEAP). The theoretical aspects of the non-linear formulations have been briefly described and the model of the rolling process has been outlined here. The implemented non-linear formulations have been compared with existing analytical, numerical and experimental solutions. Since no such results are available in the literature to compare the response of the rolling model, several experiments have been conducted on aluminum 6061 disks. The experimental results and their numerical counterparts have been included with discussion on the similarities and differences in the two. Finally, the applicability of NOFEAP to modelling the deformations in gear rolling has been demonstrated by modelling the deformations in the leading and the trailing sides of a gear tooth when rolled against a hard die. |
