Testing refractories

Figure 9.5 Schematic of the hot-wire thermal conductivity test. Refractory bricks would be of the same size as in Figure 9.3.

Keywords Stillwater Mining Company, Ca-ferritic slag. Magnesia-chromite bricks. Rotary kiln. Corrosion resistance test. Refractories, RHl... 

Table 10.20. ASTM standards for testing refractories ASTM standard Description...

ASTM C-16 Load-testing refractory brick at high temperatures... 

Baudran Expansion Apparatus. A device for measuring the thermal expansion of ceramics up to 1500 C expansion of the test-piece is directly transmitted by a lever system to an inductive displacement detector. This procedure is used for testing refractories (B.S. 1902, Pt. lA) it was devised by A. Baudran (Bull. Soc. Franc. Ceram. (27), 13, 1955). Baume Degrees (°Be). A system, introduced by a Frenchman, A. Baume, in 1768 for designating the specific... 

Slag Attack Tests. Refractories are attacked by the corrosive slags formed during metallurgical processes. Various simulative tests have been devised to assess the resistance of refractories to slag attack. 

For a more rapid method see hot-wire method for rapid, transient heat flow methods see thermal diffusivity. Thermal Ceding Test Refractories subject to repeated changes in temperature (thermal cycling) lose strength. ASTM... 

BS 1902-3.16 1990. Methods of testing refractory materials, general and textural properties Determination of pore size distribution (method 1902-316). 

Laboratory corrosion testing has been in existence for many years, and yet there is no uniformity in these attempts to evaluate the corrosion resistance of specific refractory for specific conditions. Roughly, corrosion tests may be divided into static and dynamic tests. The term static usually means that the corrosive liquid is stationary, it doesn t move against the tested refractory, and the system corrosive liquid-refractory will tend to reach equilibrium. During a dynamic test, the corrosive liquid moves against the refractory surface and the thermodynamic and chemical equilibria wmi t be reached. 

Another division is the cup of immersion testing. With the cup test, the conditions are stationary. If the tested refractory rods are immersed in the corrosive melt, the conditions are close to stationary. If the immersed tested rods are rotating in the corrosive melt (or probably are moving up and down), the conditions are dynamic. 

ASTM C768-99. Withdrawn standard ASTM C768-99 standard practice for drip slag testing refractory materials at high temperature (withdrawn 2004). 

British Standard Institute. BS 1902-1A 1966 Methods of testing refractory materials Sampling and physical tests, London. 

A controlled environment is necessary for testing refractory metals at elevated temperature (i.e. a high purity vacuttm). 

Unfortunately, an applicable uniform standard for the sampling and testing refractory gunning materials does not exist so far in Europe. Nevertheless, it is quite common to gun panels or plates. After a subsequent curing time has elapsed, which depends on the specific material, samples are cut out of a panel like that shown in Figure 9. 

Testing refractory materials is therefore an essential step in this selection and improvement process. 

Wolters D. Testing refractories in reducing and non oxidising atmospheres. Ind Cer-amique 1982 (766) 804-808. 

Refractory metal alloy core is protected from impurities in the external environment for simplified ground based testing. Refractory metal alloys are susceptible to radiation hardening and embrittlement at low temperatures. bmitinQ thermal cycling. 

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