Shock resistance, refractories

W2B5 of molten metals, thermal shock resistance, refractoriness, thermal conductivity Heat-resistant alloys [440] 1960... 

The resistance against thermal spalling of fireclay and high alumina brick is indicated in Table 5. No standard test has been adopted for basic brick. Refractories composed of 100% magnesia exhibit poor thermal shock resistance, which is improved by addition of chrome ore. So-called direct bonded basic brick, composed of magnesia and chrome additions, exhibits good thermal shock resistance. 

Alumina—graphite refractories, almost all continuous casting ware, have come into much greater use as continuous casting has spread in steelmaking. These refractories are used in shrouds that conduct the molten metal from the ladle to the tundish, in the subentry tubes that take the metal from the tundish to the mold, in isostatically pressed stopper rods, and in shroud tubes for slab and bloom casters. The alumina—graphite compositions are used in these products because of the thermal-shock resistance and corrosion resistance they impart to the product. 

Thermomechanical properties, e.g. softening under load, creep in compression, refractoriness under load and thermal shock resistance. 

Aksel, C., Davidge, R.W., Warren, P.D. and Riley, F.L., Investigation of thermal shock resistance in model magnesia-spinel refractory materials , in IV Ceramic Congress, Proceedings Book, Part 1, Eskiflehir, Turkey, 1998. 

Chaklader, A.C.D. and Bradley, F., Thermal shock resistance parameters and their application to refractories , UNITECR 89, 1989. 

For reformer outlet manifolds the normal metallurgy choice is a wrought type of Alloy 800 H. It has sufficient ductility and thermal-shock resistance during startup and shutdown. The cast version of Alloy 800 H provides a cost-effective, alternate material with a higher creep-rupture strength, low tendency for embrittlement and good ductility. Hot reformed-gas transfer lines are usually refractory-lined with an interior of Alloy 800 sheathing88. 

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