Mullite

Mullites (3Al2O3 • 2SiO2) are refractory oxide materials combining low thermal expansion, good mechanical strength and resilience at elevated temperatures. McDanel Advanced Ceramic Technologies LLC mullites are formulated to produce dense shapes, some in a glass matrix in order to yield maximum thermal shock resistance and good strength.

Grades Typical Uses
MV20 is a dense mullite in a glassy matrix formulated to offer a high quality economical insulating tubing for thermocouple applications. Insulators in oxidizing conditions for base and noble metal thermocouples used in conditions up to 1450°C.
MV30 is an extremely versatile and economical material. Its workability allows an extensive range and flexibility in fabrication. It is well suited for the casting of special shapes. Thermocouple protection tubes, target and sight tubes, furnace muffles, diffusion liners, combustion tubes, radiant furnace tubes and kiln rollers.



Alumina

Aluminas (Al2O3) are generally more chemically resistant, harder, stronger and more refractory than mullite.

Grades Typical Uses
998 99.8% alumina can be used at operating temperatures to 1950°C in both oxidizing and reducing atmospheres. Tubes have been evacuated to 10-7 Torr at 1500°C. 998 proves inert to hydrogen, carbon and refractory metals in many severe situations. Noble metal thermocouple protection, furnace tubes, high temperature vacuum furnaces, heat treating furnace rollers, radiant tubes, laser tubes, corona treater tubes and ozone generators.
AP35 99.0% alumina is a high purity body designed for the extrusion manufacturing process. It offers good insulating characteristics and high temperature capabilities. Corrosive environments and electrical insulation applications. Noble metal thermocouples and diffusion furnace profile couples, laser wave guides and RTD's.
AV30 96% alumina is an exceptionally tough alumina at an economical price designed especially for wear resistant applications. Abrasive and corrosive environments.



Zirconia

Zirconias (ZrO2) are extremely refractory materials. They possess excellent chemical inertness and corrosion resistance at temperatures well above the melting point of alumina. McDanel Advanced Ceramic Technologies LLC zirconias are stabilized in the cubic crystal structure to avoid cracking and mechanical weakening during heating and cooling. In addition to their refractoriness, they offer low thermal conductivity and are electrical conductors above 800°C. They also possess the unique ability to allow oxygen ions to move freely through the crystal structure above 600°C.

Grades Typical Uses
Z105 is a fine grained, high density, cubic crystal, yttria (10.5%) stabilized zirconia. It is an excellent general purpose zirconia. Available by quotation. Oxygen sensors, thermocouple protection tubes, furnace muffles, liners, crucibles, high temperature heating element support.



Sialon

McDanel Advanced Ceramic Technologies LLC SiAlON is an alloy of silicon nitride and aluminum oxide. This superior refractory material has the combined properties of silicon nitride (high strength, hardness, fracture toughness and low thermal expansion) and aluminum oxide (corrosion resistance, chemically inert, high temperature capabilities and oxidation resistance.

Most refractory products are capable of surviving one or two specific environments that typically involve high temperature, mechanical abuse, corrosion, wear or electrical resistance. McDanel Advanced Ceramic Technologies LLC SiAlON has the capability to withstand all of these environments - at the same time!

Grades Typical Uses
SiAlON Good for molten metal applications, high wear or high impact environments up to 1250°C. It is non-wetting for most nonferrous metals, gas tight, chemically inert, resistant to corrosion and metal attack and features high strength hardness and thermal shock resistance.