Potential of SIC as a heat Exchange Material in Combined Cycle Plants
The short and long term mechanical properties of a sintered silicon carbide intended as a heat exchanger material have been investigated. The short term strength shows an acceptable scatter characterized by a Weibull modulus of seven from room temperature of up to 1400 degrees celsius. In the time dependent regime failure occurs by subcritical crack growth from surface located inherent defects at high stresses. Below a threshold stress oxidation blunting of these surface defects occurs and causes a transition from subcritical crack growth to diffusion creep as life-limiting mechanism. Unlike other ceramics, the threshold stress for subcritical crack growth falls within the low probability range of fast fracture. Failure mechanism maps presenting the life-limiting mechanisms of the investigated sintered silicon carbide over a range of stresses and temperatures are presented.
Bibliographic Reference: Paper presented: 9th CIMTEC, Florence (IT), 14-19th June (1999)
Availability: Available free of charge from CCR Ispra (IT)
Record Number: 199911363 / Last updated on: 1999-09-10
Original language: en
Available languages: en