Papers by Keyword: TiN Nanoparticles

Abstract: Oxide free Tin nanoparticles were synthesized from a chemical reduction method. Their morphological and thermal characterizations were studied in this paper. The X-ray diffraction (XRD) study showed that no oxides of Tin nanoparticles were formed. The thermal characterization by differential scanning calorimetry (DSC) exhibited the size dependency of the melting points. The melting point was as low as 202.16°C.

Abstract: Tin nanoparticles were synthesized through compulsive reduction using a Tin(II) 2-ethylhexanoate precursor, and the effect of reductant (sodium borohydride) amount on the size distribution of the particles was surveyed. Issues caused by the absence of a capping agent (polyvinyl pyrrolidone) were similarly examined. An excessive amount of dissolved sodium borohydride caused variations in the tin nanoparticle sizes, from a few nanometers to several tens of nanometers. The formation of abnormally large particles was attributed to the vigorous coagulation among smaller tin particles. In the tin nanoparticles synthesized without polyvinyl pyrrolidone, an exceptionally wide size distribution was observed owing to irregularly coagulated and aggregated large particles.

Abstract: TiN nanoparticle-dispersed Si3N4 ceramics is one of the typical ceramics used for bearing applications. Because larger TiN particles considerably damage the mating metallic materials, smaller TiN particles must be dispersed in Si3N4 ceramics. In this study, we fabricated TiN nanoparticle-dispersed Si3N4 ceramics from Si3N4–nano TiO2 composite particles prepared by mechanical treatment. The mechanical properties of the fabricated TiN nanoparticle-dispersed Si3N4 ceramics were evaluated. At first, TiO2 nanoparticles were dispersed in ethanol using polyethylene imide as a dispersant with a lower molecular weight. Si3N4 powder was mixed with this slurry to obtain a powder mixture. In this case, the reaggregation of the TiO2 nanoparticles during the drying process is the problem that has to be solved. In this study, TiO2 nanoparticles and Si3N4 particles were mechanically joined by a particle composer to fabricate the composite particles from the powder mixture. TiN nanoparticles were uniformly dispersed in Si3N4 ceramics by using composite powder. The bending strength of the developed Si3N4 ceramics with TiN nanoparticles was improved, and its distribution was narrow due to the homogeneous dispersion of TiN nanoparticles.