Silicon Carbide & ZTA Ceramics

Alumina covers the large majority of industrial wear duties. There are two situations where it does not, and we supply both alternatives from the same engineering team so you get an honest comparison rather than a sales pitch for whichever material we happen to stock.

Silicon carbide (SiC)

Silicon carbide is harder and more thermally conductive than alumina, which makes it the better choice where abrasion is extreme, where thermal shock is severe, or where the part is exposed to strong alkali or to hydrofluoric acid. Its weaknesses are brittleness — it tolerates impact less well than alumina — and cost.

• Choose SiC for: hydrocyclone apexes and liners, pump wear parts in aggressive slurries, kiln furniture that sees fast cycling, high-temperature nozzles, mechanical seal faces.
• Do not choose SiC for: high-impact chutes with large particles, or where the price per square metre dominates and alumina would give adequate life.

ZTA (zirconia-toughened alumina)

ZTA is alumina with 10–30% zirconia dispersed through the matrix. The zirconia particles blunt crack propagation, so the material is significantly tougher than plain alumina while keeping most of its hardness. It is the right answer where a part chips at its edges — trimming knives, cutting edges, sharp-cornered wear pieces — rather than where it wears uniformly.

• Choose ZTA for: tiles whose failure is edge chipping, ceramic cutting and trimming blades, wear parts with sharp internal corners, components that see repeated light impact.
• Do not choose ZTA for: continuous high-temperature duty above about 1,200 °C, where the zirconia phase degrades.

Choosing between alumina, SiC and ZTA

SiC and ZTA are supplied alongside our alumina range rather than made on our own primary lines, so lead times are longer than for alumina. Tell us the duty and we will say honestly whether the premium is justified.