Advanced Creep Testing of Refractories Providing New Insight into Material Behaviour

Harald Harmuth1, Romain Techer2, Dietmar Gruber3, Stefan Schachner3, Shengli Jin3, Pierre Meunier4

1 Chair of Ceramics, Montanuniversitaet Leoben/Austria
2 Calderys, Sézanne/France
3 Chair of Ceramics, Montanuniversitaet Leoben/Austria
4 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

[1] PRE-Product carbon footprint report. European Refractories Producers Federation, Brussels, September 2013, www.pre.eu [2] Paula da Luz, A.; Braulio, M.A.L.; Pandolfelli, V.C.: Refractory castable engineering. Baden-Baden 2015, 3–8 [3] Semler, C.E.: The world’s most important but least known products. Amer. Ceram. Soc. Bull. 93 (2014) [2] 34–39 [4] Semler, C.E.: Review of refractories markets and research – 2016. refractories WORLDFORUM 9 (2017) [2] 30–34 [5] Bradt, R.C.; Harmuth, H.: The fracture resistance of refractories. refractories WORLDFORUM 3 (2011) [4] 129–135 [6] Harmuth, H.; Bradt. R.C.: Investigation of refractory brittleness by fracture mechanical and fractographic methods. Interceram, Refractories Manual (2010) 6–10 [7] Miyaji, D.Y.; et al.: Fracture energy and thermal shock damage resistance of refractory castables containing eutectic aggregates. Ceramics Int. 40 (2014) [9] 15227–15239 [8] Böhm, A.; et al.: Thermal shock and thermo-mechanical behaviour of carbon-reduced and carbon-free refractories. J. of Ceram. Science and Technol. 7 (2016) [2] 155–164 [9] Zhu, T.; et al.: Fracture behaviour of low carbon MgO–C refractories using the wedge splitting test. J. of the Europ. Ceram. Soc. 37 (2017) [4] 1789–1797 [10] Preux, N.; et al.: Development of a fractography method to investigate the crack path, induced during wedge splitting test of alu mina-spinel castables. Proc. of 60 Int. Coll. on Refractories, 2017, Aachen, Germany, 108–113 [11] Jin, S.; Harmuth, H.; Gruber, D.: Compressive creep testing of refractories at elevated loads – Device, material law and evaluation techniques. J. of the Europ. Ceram. Soc. 34 (2014) [5] 4037–4042 [12] FactSage 7.0. http://www.factsage.com [13] De Jonghe, L.C.; Rahaman, M.N.: Handbook of Ceramics, S. Somiya, Ed., Chapter 4.1, Sintering of ceramics. Amsterdam 2003

Copyright

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