Hot-Pressed Silicon Nitride with Various Lanthanide Oxides as Sintering Additives

Low Temperature Sintering Additives for Silicon Nitride

This work deals with sintering additives for the low temperature pressureless sintering of Si3N4, via a transient liquid technique. Much attention has been given to the development of a sintering process using low-cost Si3N4 powder (Silzot HQ, Germany) as the starting material and employing sintering additives which are also both economically attractive and enable sintering at low temperatures....

Modeling the strain-rate dependence of fatigue life of hot- pressed silicon nitride

This paper presents the results of a micromechanical model used to explain the strain-rate dependence of the compression fatigue lives of amorphous and crystalline grain boundary phase; denoted by ABP and CBP silicon nitrides, respectively. When the strain-rate is changed from 400 to 0.01/s, the fatigue lives of both materials, evaluated at a peak stress of 3.2 GPa, increased by more than two o...

Dynamic Multiaxial Response of a Hot-Pressed Aluminum Nitride

Interfacial structure in silicon nitride sintered with lanthanide oxide

Three independent research groups present a comparison of their structural analyses of prismatic interfaces in silicon nitride densified with the aid of lanthanide oxide Ln2O3. All three groups obtained scanning transmission electron microscope images which clearly reveal the presence of well-defined Ln segregation sites at the interfaces, and, moreover, reveal that these segregation sites are ...

Microstructure and Fracture Toughness of Hot-Pressed Silicon Carbide Reinforced with Silicon Carbide Whisker

The effects of p-Sic whisker addition on the microstructural evolution and fracture toughness (K,c) of hot-pressed SIC were investigated. Most of the whiskers added disappeared during the densification process by transformation into the a-phase. The remaining whiskers acted as nuclei for grain growth, resulting in the formation of large tabular grains around the whiskers. The tabular grains aro...