Patent ID: 7964296
Filing Date: 2011-06-21
Classification: C04B,Y10T

Abstract:
1. A fully dense multi-component Si 3 N 4 monolith having a matrix and indistinguishable joints made by simultaneously joining and hot pressing a plurality of RBSN parts, said Si 3 N 4 monolith comprising at least 85% by weight β-Si 3 N 4 and up to 15% by weight of a predominantly amorphous binder phase and having a hot pressed volume of greater than 250 cm 3 and the following properties both in the joints and in the matrix material: (a) bulk density of at least 99.0% of theoretical; (b) fracture toughness of at least 4.5 MPa·m (c) Vickers hardness HV-5 greater than 1500 kg/mm (d) elastic modulus of at least 300 GPa; and (e) four-point flexural strength of at least 700 MPa.