Finite element calculation of thermomechanical stresses in candidate ceramic components for press and blow moulds

The alternative of replacing metal mould equipment for the manufacture of h ollow glass items in an IS machine by mould components produced from techni cal ceramic materials was investigated. As a first step finite element calc ulations were introduced with respect to the selection of relevant candidat e materials from the family of technical ceramics. By using such calculatio ns it was possible to estimate thermomechanical stresses and rule out a num ber of ceramics that would be otherwise subjected to a large risk of fractu re. Experiments on industrial IS machines proved the selected ceramic press plungers to be mechanically functional without fracture as predicted by th e calculations. Adhesive wear of the ceramic press plungers however turned out to be the major functional problem prohibiting the toe of ceramics for these applications.