Finite Element Analysis of the Diametral Test of Polymer Moldings

Abstract

A finite element analysis of the diametral test is presented and the results are compared with an elastic analysis and with diametral tests of molded pyrrone disks. Both the elastic and the finite element analysis gave similar stresses for points near the center of the disk. Near the points of loading, however, the elastic analysis gave infinitely high stresses whereas the finite element analysis gave high but finite stresses. A simulated fracture was made using the finite element analysis. The fracture began at the center of the disk and propagated toward the loading points. As the fracture approached the loading points, the finite element analysis indicated the formation of four secondary fracture sites in the disk. These sites were a normal development for a soft loading system. The existence and location of the secondary fracture sites was confirmed by diametral tests of molded pyrrone disks.