Simulation of Refractory Fracture as a Tool for Advanced Material Testing

Abstract:

The work presented here deals with simulation assisted evaluation of fracture testing of ordinary ceramic refractory materials. Two tests are applied. One of them, a wedge splitting test, is already established for this purpose. An inverse evaluation procedure was developed to derive more information from the test results: It enables the simultaneous determination of the specific fracture energy, the tensile strength and the Young’s modulus. Moreover specific fracture energy can also be determined in the case that the test has to be interrupted at some residual load due to relatively low material brittleness. The other test method, a laser irradiation disc test, was developed in order to determine specific fracture energy and tensile strength for fine ceramic refractory materials behaving relatively brittle. From the time elapsed until crack initiation occurs (t₁) and a stable/instable transition of crack propagation takes place (t₂), respectively, the tensile strength and the specific fracture energy are calculated based on a simulation of the mode I fracture behavior which applies the fictitious crack model according to Hillerborg.

• Periodical: Advances in Science and Technology (Volume 92)
• Pages: 232-241
• DOI: https://doi.org/10.4028/www.scientific.net/AST.92.232
• Online since: October 2014
• Authors: Dietmar Gruber*, Sheng Li Jin, Harald Harmuth
• Keywords: Disc Test, Fracture, Inverse Evaluation, Refractory, Simulation, Wedge Splitting Test

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