Fig. 1 shows phase evolution in mixtures of Si and CB (with the molar ratio of 1/8) (referred to as the 1/8 mixture hereafter) after 6 h firing in molten salt containing 20 wt% NaF, at various temperatures. At 900 °C no SiC was formed and only unreacted carbon (indicated by the broad peak) and Si remained, whereas at 1000 °C SiC started to appear and Si peaks concurrently decreased. On increasing the temperature to 1100 °C, Si disappeared and only SiC was seen along with unreacted carbon. On further increasing the temperature to 1200 °C, no further phase changes were seen, though the peaks of SiC became slightly sharper, indicating its enhanced crystallinity or increased size.