Silicon nitride ceramics with sintering oxide additives obtained from organoyttriumoxanealumoxane

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....

Orthopedic applications of silicon nitride ceramics.

Silicon nitride (Si(3)N(4)) is a ceramic material developed for industrial applications that demand high strength and fracture resistance under extreme operating conditions. Recently, Si(3)N(4) has been used as an orthopedic biomaterial, to promote bone fusion in spinal surgery and to develop bearings that can improve the wear and longevity of prosthetic hip and knee joints. Si(3)N(4) has been ...

Optically transparent ceramics by spark plasma sintering of oxide nanoparticles

Microstructure of Spark Plasma-Sintered Silicon Nitride Ceramics

The microstructure and phase composition of the high-content Al2O3-Y2O3-doped spark plasma-sintered silicon nitride were investigated. Fully dense silicon nitride ceramics with a typical α-Si3N4 equiaxed structure with average grain size from 200 to 530 nm, high elastic modulus of 288 GPa, and high hardness of 2038 HV were spark plasma sintered (SPSed) at 1550 °C. Silicon nitride with elongated...

Interface structure and atomic bonding characteristics in silicon nitride ceramics.

Direct atomic resolution images have been obtained that illustrate how a range of rare-earth atoms bond to the interface between the intergranular phase and the matrix grains in an advanced silicon nitride ceramic. It has been found that each rare-earth atom bonds to the interface at a different location, depending on atom size, electronic configuration, and the presence of oxygen at the interf...