Abstract In this study, kinetics of boride layers formed on the surface of ferritic GGG 40.3 ductile iron were investigated by conducting a series of experiments in Ekabor I powder at 850, 900 and 950 °C treatment temperature for 1, 2 and 4 h by using Ekabor I powder. Also, box boronizing was carried out at 950 °C for 4 h with Ekabor II powder to investigate effect of powder size. At the same time, it has been investigated whether or not iron boride layers were obtained using different powder mixtures instead of commercial powder (SiC + KBF4 + B4C). Also, the 85 wt.-% B4C + 15 wt.-% Na2CO3 powder mixture has been used. The study was aimed to inhibit the release of fluorine gas and to perform environmentally friendly working. After the experiments, it turned out that the depth of boride layers depending on treatment temperature and time ranged from 38 to 198 μm. The presence of borides were confirmed by X-ray diffraction, optical microscopy and scanning electron microscopy. A saw tooth shape morphology of boride layers has been detected in optical microscopy and scanning electron microscopy.