MORGAN ADVANCED MATERIALS: Silicon Nitride Ceramic Coating
A new silicon nitride (Si3N4) coating for ceramic components is now available from Morgan Advanced Materials. Haldenwanger® HalCoat™ comprises two grades of Si3N4 coating that can reportedly be applied to a variety of Morgan products, including fused silica-, silicon carbide- and mullite-bonded ceramics to offer a host of benefits ranging from enhancing durability to avoiding contamination within a crucible.
Designed for fused silica rollers in applications such as hot stamping roller kilns, the standard purity of the first HalCoat grade reportedly helps prevent alloy buildup in the annealing process. The coating’s anti-wetting properties can extend the longevity of silica rollers, which are typically subject to layers of AlSi12 alloy layers forming on the surface.
The second HalCoat grade has been developed for the coating of fused silica crucibles. “The latest advances in crucible technology utilize electro-magnetic fields to fine-tune the flow characteristics of melting silicon, which is invaluable in controlling the directional solidification of multi-crystalline photovoltaic silicon ingots,” said Michael Rozumek, R&D Director for the Haldenwanger products business at Morgan Advanced Materials. “However, a knock-on effect is the considerable increase in mechanical wear within the crucible. Using HalCoat to treat these surfaces helps avoid delamination of the coating and therefore decreases the risk of contamination in the melt.”
For more information, visit www.morganadvancedmaterials.com.