Reliability study of ceramic matrix composites based on clinker portland doped with alumina and silica

A study was made of the Weibull modulus of white clinker portland reinforce d with alumina and silica. The Weibull distribution was introduced as a way of measuring the reliability of materials through the slope or shape param eter, known as Weibull modulus, and it is used as a reference and estimatio n of the probability of failure. The manufacturing process of composite mat erials (3, 6 and 9% Al2O3 and SiO2 by weight) includes mixing in a ball mil l, cold isostatic pressing in wet bag at 180 MPa and sintering at 1400 degr ees C in air. Bending strength was used as the key property for measuring t he Weibull modulus using more than 20 tests in all cases. The correlation c oefficients obtained in all the estimations for the studied materials are a bove 95%. These ceramic matrix composite (CMCs) materials present a high We ibull modulus (in some materials about 26) and better behaviour than plain white clinker portland. Most results are above typical values of the conven tional and advanced ceramics (between 5 and 15). Microstructural analysis w as carried out to explain the reliable behaviour of these materials, a beha viour that could make them very interesting for structural applications. (C ) 2000 Kluwer Academic Publishers.