Wesgo VX Super Refractory

Typical are furnace and induction brazing, sintering of powder metal compacts, calcining of powders and components of high-temperature systems subjected to rapid temperature changes. While its chief distinguishing characteristic is its almost complete freedom from cracking or spalling due to rapid temperature fluctuations, it also possesses the following valuable properties:

• Extremely low thermal expansion (6 x 107 per degree C at 1000º C)
• Immune to all furnace atmospheres and free of metal-contaminating impurities (contains no readily reducible oxides)
• Porosity is variable within certain limits… it averages 21%
• Low specific gravity (1.6 – 1.7)
• No loss of strength at high temperatures (flexural strength at 1000° C is higher than at room temperature)
• Low thermal conductivity (.0025 cal/sec/cm2/cm/degree C)
• Specific heat is 0.24 cal/gram at 100° C; 0.27 at 1000°C
• High electrical resistivity (0.7 x 106 ohms per cm3 at 1000° C)
• Dielectic constant is 3.6 at 60 cycles

While the maximum recommended temperature for continuous service is 1200° C for intermittent service such as induction melting or other short cycle heating operations, the Wesgo "VX" Super Refractory can be used up to 1450° C. A number of shapes…boats, slabs, short tubes, crucibles, etc. are available from stock. When the necessary mold costs are economically indicated, almost any special shape can be molded to close dimensional tolerances. Wesgo "VX" Super Refractory shapes can be readily ground with Silicon Carbide wheels and drilled with carbide-tipped tools.