The special strength-testing methods have been established for refractory ceramics, which are of a mostly heterogeneous composition.
The refractoriness under load (RUL) and Creep in Compression (CIC) identify the deformation resistance of a test piece under a defined load and temperature/time factors, and can be determined with one instrument without retrofitting. By reducing the load on the test pieces to negligible values as compared to the surface of the test piece), precise dilatometer measurements on large and even inhomogeneous samples can be carried out in the RUL 421 at temperatures up to 1700°C.
The modulus of rupture at high temperatures (HMOR) is determined with a hot modulus of rupture tester. The determination of the maximum load at high temperatures is a property which, along with other thermophysical properties, is an important parameter for quality control and development of furnace linings. The available models of the HMOR 422 hot modulus of rupture apparatus are used to measure the failure load as well as bending under load or deformation force, using a 3 point bending test on the refractory.
The melting behaviour of these heterogeneous ceramics is determined indirectly through comparison with so-called Seger cones (PCE-Pyrometric Cone Equivalent). In the PCE 428, the pyrometric cone equivalent can be ascertained visually up to a maximum temperature of 1700°C. Reference cones with well-established pyrometric cone equivalents at temperature intervals of 10°C and above along with the test cones made from the sample material are heated in the same furnace, so that it is possible to make an accurate comparative temperature determination for the softening point of the refractory material to within approx. 20°C.
Also available is a thermal conductivity tester which works according to the hot-wire method. It is especially designed for the investigation of refractory rock. The measuring cross, parallel wire, and T(R) methods can be used with the instrument. The TCT 426 is indispensable for the efficient use of energy in industrial kiln engineering with refractories.
These refractory testing instruments all conform to the pertinent instrument and applications standards. They are available in Australia and New Zealand from Technical and Scientific Equipment (TSE).