ABSTRACT
In describing failures there are many factors and characteristics to consider. One of which is the failure profile-for general principles see Figure 1. This profile depends on the failure causes; the failure manifestations (namely the ways and mechanisms of failure) and the failure consequence. These failure causes can be design failures, manufacturing failures, overstress failures, misuse failures or degradation failures. The failure manifestations may be random, gradual, sudden, common cause, primary, secondary, intrinsic or extrinsic. The consequences could be insignificant, marginal, minor, major, critical, catastrophic or also scaled differently. For more
1 INTRODUCTION
Failure is a term widely used in technical practice especially concerning dependability theory. It is inevitable to realize that a failure is of key importance for operation and function of technical items. Theory and practice in particular shows that failures occur under different situations, various circumstances, ranging conditions, etc. For safety and reliability practitioners failure is a basic term in theory, and it is key and essential for observing stochastic relations of item behaviour. It is an event which is used in probability theories on a general level; the term probability event is used. In dependability theory it is necessary to realize the fact of failure as a stochastic term, to understand its meaning, and to understand other links. What we need to catch up here is the meaning and relation to safety. The requirements on polymer composites are to be failure safe or to prevent further failure propagations-once failures occur. For more details see e.g. Elsayed 1996, Meeker & Luis 1998, Stodola et al. 2013, Werbinska-Wojciechowska 2013, Werbińska 2007.
