Microporous Calcium Titanium Phosphate glass-ceramics have many uses in high-tech industries. For example, they have applications in catalysts industry. In this study, different molar percentages of alumina were added to a glass with P2O5 30, CaO 45, TiO2 25 (mol%) composition. The samples were melted at 1350°C and crystallization heat treatment was performed on...

The silver toughened alumina ceramics, which were fabricated via a conventional ceramic processing route using commercially available alumina and silver oxide powders as the starting materials, exhibit a higher fracture toughness (6 to 9 MPamo.5) than the monolithic alumina ceramic ( 2.5 to 3.0 MPamo.5). The weak interfacial bonding between the silver inclusions and the alumina matrix is charac...

A general method for brazing ceramics to metals using a compliant metallic foam as a buffer layer has been developed. Using stainless steel foams, bonds between alumina and 316 stainless steel with shear strengths up to 33 MPa have been achieved. The resultant ductility enhances the resistance of the joint to thermal cycling; AlN-Inconel 600 bonds exhibited good thermal shock resistance. Alumin...

The reaction-bonded aluminum oxide (RBAO) process utilizes the oxidation of attrition-milled Al/Al2O3/ZrO2 powder compacts, that are heat treated in air, to make alumina-based ceramics. A simultaneous mass and energy balance has been used to model the propagation of the ignition front that has been observed during reaction-bonding. The model is used to determine conditions under which ignition ...

Since hydroxyapatite has excellent biocompatibility and bone bonding ability, porous hydroxyapatite ceramics have been intensively studied. However, porous hydroxyapatite bodies are mechanically weak and brittle, which makes shaping and implantation difficult. One way to solve this problem is to introduce a strong porous network onto which hydroxyapatite coating is applied. In this study, porou...

Alumina is the most widely used oxide ceramic material. It exists in many metastable forms which lead upon severe thermal treatment towards the thermodynamically stable phase alpha. Sintering of alumina generally takes part in a minimum of two stages: i) phase transition(s) towards the stable phase alpha and ii) densification of this phase alpha. The former step(s), linked to transition phase(s...