Advanced Creep Testing of Refractories Providing New Insight into Material Behaviour
1 Chair of Ceramics, Montanuniversitaet Leoben/Austria
2 Calderys, Sézanne/France
Revision 17.01.2018, 01.02.2018
Volume 10, Issue 2, Pages 63 - 67
Abstract
Feasible high temperature testing approaches for ordinary ceramic refractory materials are of importance to understand material behaviour in service and further facilitate the material development. Aside from the wedge splitting test and modifed shear test applied to investigate the tensile and shear failure respectively, an advanced high temperature compressive creep testing device was developed to characterize the creep behaviour of ordinary ceramic refractory materials. The application of rather low preload during heating up procedure and creep measurement on the cylindrical surface of specimens allows for determining the creep onset and deformation accurately. The study of an ultralow cement alumina castable demonstrated that the creep of the virgin castable below 1500 °C is overruled by sintering, which is sensitive to the preheating conditions of preload, dwell time and temperature. Caution shall be taken on the creep testing conditions for monolithics, and the consideration of service conditions is necessary. The identifcation of sintering contribution to the deformation during creep testing is also essential to gain advanced understanding on the thermomechanical behaviour of industrial vessel refractory linings.
Keywords
creep behaviour, monolithic refractories
References
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