Mechanical properties of oriented mica glass ceramic

The mechanical properties of extrusion oriented mica glass ceramic were studied. Anisotropy caused by the alignment of the basal planes of phlogopite crystals along the extrusion axis was observed. Fracture toughness varied in direction by about 350%, Knoop-microhardness by about 30% and Young's modulus by about 15%. By comparison with the randomly oriented mica glass ceramic, an enhancement of the mechanical properties was measured in the direction perpendicular to the extrusion axis. The influence of the crystal alignment on mechanical properties and machineability is discussed. (C) 1997 Elsevier Science B.V.