Effect of heating temperature of expandable graphite on amorphization behavior of powder expanded graphite-Fe mixtures by ball-milling

Three expanded graphites, EG1, EG2 and EG3 that were prepared by rapid heating expandable graphite to 600, 800 and 1000 °C, respectively, were ball-milled in a high-energy mill (planetary-type) in an air atmosphere with 16.7% iron powder addition. The X-ray diffraction patterns of the products show that the amorphization process of the powder EG-Fe mixtures during ball-milling is accelerated with increasing the heating temperature of expandable graphite. In addition, amorphous EG-Fe system and Fe3C phase are formed in the ball-milled EG3-Fe. Compared with the amorphization process of EGs without iron addition during ball-milling, the presence of iron restrains the process of EG1 in rate, but it promotes the process of EG3.

Three expanded graphites, EG1, EG2 and EG3 that were prepared by rapid heating expandable graphite to 600, 800 and 1000 °C, respectively, were ball-milled for 60, 80 and 100 h in the presence of iron. The amorphization process of the milled EG-Fe systems is accelerated with increasing the heating temperature of expandable graphite.Figure optionsDownload as PowerPoint slideResearch highlights
► We investigated the amorphization process of three EG-Fe mixtures during ball-milling.
► Increasing the heating temperature of expandable graphite accelerated the process of the mixtures.
► The additive Fe restrained the process of EG1 but promoted the process of EG3.