A novel technique for production of nano-crystalline mono tungsten carbide single phase via mechanical alloying

Due to simultaneous synthesis of WC and W2C phases in most of the synthesis processes and lower mechanical properties of W2C than WC, in this work the possibility of production of nano-crystalline WC single phase as a useful refractory ceramic by means of mechanical alloying has been investigated. The raw materials containing W and C with WC were milled in a planetary ball mill. The sampling has been done in different times. As it was expected, XRD studies showed that after 75 h of milling the WC with W2C were produced. By adding WC to the raw materials in the beginning of the process it led to the fact that after 50 h of milling WC was synthesized only without any other phases which remained stable at the higher times while milling. During broadening of XRD peaks, the size of synthesized crystalline WC was estimated in the order of nano-meter. Crystalline size and mean strain of synthesized WC in the system without additive were higher and lower than the system containing WC, respectively.

► By adding WC to mixture of tungsten and carbon black unlike the system which does not contain any additive, it can lead to synthesized mono carbide tungsten. ► However, the synthesize time has been reduced significantly. ► Crystalline size of two systems were in nano-meter scale, this amount in system contain primary WC which was smaller than system without WC.