USE OF NUMERICAL-METHODS TO CALCULATE THE RELIABILITY OF COMPONENTS FABRICATED WITH FRAGILE MATERIALS

Some materials are fragile due to the great number of microcraks produ ced during their conformation processes, for example ceramics. That is the reason why, along these years different design criteria have been proposed to calculate these fragile materials: specially ceramics, ba sed in probabilistic theories. A programme to calculate ceramic compon ents with these criteria has been developed in the I.M.W. (Clausthal, Germany). This program works as a subprocessor of the finite element p rogram MARC, and can analyse the probability of survival of a componen t with three general criteria and with fracture mechanics criteria (el even when calculating volume components and six for surface ones). Tho se criteria have been implemented also to calculate the probability of survival with applied loads during time intervals and to calculate se curity factors.