Porous wicks for use in a loop heat pipe were sintered from copper and Monel powder. These wicks were characterized in terms of their shrinkage, porosity, thermal conductivity, liquid permeability and maximum capillary pressure. The effect of fabrication parameters (particle size and sintering conditions) on these properties was studied. Shrinkage was found to increase with increasing sintering...

Pure HA and 1, 3, 5, and 10 vol% multiwalled carbon nanotube- (MWNT-) reinforced hydroxyapatite (HA) were consolidated using a spark plasma sintering (SPS) technique. The relative density of pure HA increased with increasing sintering temperature, but that of the MWNT/HA composite reached almost full density at 900°C, and then decreased with further increases in sintering temperature. The relat...

Residue powders resulting from cutting and machining operations in slate quarries were processed by a press and sintering route to manufacture ceramic products such as flooring and roofing tiles. The first part of this work consisted of a laboratory study carried out by uniaxially pressing the powders to shape and sintering in air using a muffle type furnace. A plan of sintering experiments was...

Sintering is a key technology for processing ceramic and metallic powders into solid objects of complex geometry, particularly in the burgeoning field of energy storage materials. The modeling of sintering processes, however, has not kept pace with applications. Conventional models, which assume ideal arrangements of constituent powders while ignoring their underlying crystallinity, achieve at ...

Shrinkage behavior and crack formation during firing have been investigated for Al2O3/Ce-TZP composites that have been fabricated by colloidal rolling and folding. These composites show improved sinterability and sinter isotropically after repeated rolling. Interface instability in rolling creates corrugated interfaces with large layer waviness; therefore, rolling can substantially alleviate th...

In this article, we report a new route to synthesize diamond by converting "solid" carbon nanofibers with a Spark Plasma Sintering system under low temperature and pressure (even at atmospheric pressure). Well-crystallized diamond crystals are obtained at the tips of the carbon nanofibers after sintering at 1500 °C and atmospheric pressure. Combining with scanning electron microscopy, transmiss...

Hydroxyapatite (Ca10(PO4)6(OH)2) (HAp) is a very attractive material for human tissue implantation, beacuse it makes up ~69% of the weight of bone [1]. Unfortunately HAp posses low mechanical properties (strength, fracture toughness), which is a barrier to its applications in load-bearing situations [2]. The mechanical properties of HAp composites, is based on the synthesis of composites and th...

An aberration-corrected JEOL 2200FS scanning-transmission electron microscope (STEM), equipped with a high-angle annular dark-field detector (HAADF), is used to monitor the coalescence and sintering of Pt nanoparticles with an average diameter of 2.8 nm. This in situ STEM capability is combined with an analysis methodology that together allows direct measurements of mass transport phenomena tha...

Recent research has been significantly increased our fundamental understanding of microwave interactions with materials. Thermal absorption has been demonstrated to result from simultaneous action of multiple dissipation mechanisms during processing. In addition, it has been conclusively established that strong microwave fields exert a non-thermal driving force during sintering. This force acts...

The aim of the present investigation was to formulate thermally sintered floating tablets of propranolol HCl, and to study the effect of sintering conditions on drug release, as well as their in vitro buoyancy properties. A hydrophilic polymer, polyethylene oxide, was selected as a sintered polymer to retard the drug release. The formulations were prepared by a direct compression method and wer...