An investigation on the application of process control agents in the preparation and consolidation behavior of nanocrystalline silver by mechanochemical method

In this paper, the effect of various amounts and types of process control agent (PCA), i.e., stearic acid (SA) and ethylene bis-stearamide (EBS), in the production and consolidation behavior of nanocrystalline silver prepared by mechanochemical reduction of Ag2O by graphite was studied. The structural evolution and morphology of powders were investigated using XRD, HRSEM and particle size analyzer techniques. The results showed the nanocrystalline Ag formed after 25 h of milling and the addition of PCA prolonged the synthesis process time. Also, the effect of EBS on prevention of the excessive cold welding of ultra-fine Ag particles in the final stages of milling was more serious than SA. In fact, the presence of PCA effectively inhibited the creation of coarse Ag particles and finally decreased the crystallite size to 14 nm. Moreover, with the addition of PCAs, the Brinell hardness of sintered Ag samples was considerably increased.

The effect of various amounts and types of process control agent, i.e., stearic acid (SA) and ethylene bis-stearamide (EBS), in the production and consolidation behavior of nanocrystalline silver prepared by mechanochemical reduction of Ag2O by graphite was studied.Figure optionsDownload as PowerPoint slideHighlights
► A novel technique for synthesis of silver nanoparticles.
► The production of highly spherical particles of silver in the nanoscale regime.
► Characterization of products by HRSEM and XRD.
► Determination of the sintering behavior of silver nanoparticles.