MCROWAVE-ASSISTED COMBUSTON SYNTHESS IN A MECHANCALLY ACTIVATED T-B4C SYSTEM

The TiB-TiC in-situ nanocomposite has been fabricated by different techniques. In this work, the mechanical activation process has been used to aid microwave-assisted combustion synthesis (MACS) to produce the TiB2-TiC in-situ nanocomposite. For this purpose, the thermite mixture of Ti and boron carbide (BC) powders were used as the raw materials, and were mechanically activated at different milling times. The results of X-ray phase analysis of the mechanically activated samples after combustion synthesis showed that the TiB2-TiC in-situ nanocomposite has been successfully fabricated by thermal explosion mode of combustion synthesis in microwave, while no combustion synthesis occurred for the unmilled sample. Also, it was found that by increasing the milling time from 1 to 9 h, the purity of the final products has been increased. Finally, in order to have a good understanding about the in-situ formation of such ceramic nanocomposites, a reaction mechanism was proposed based on the experimental results.

کلیدواژه ها:

Boron carbide ، Mechanical activation ، Microwave-assisted combustion synthesis ، Nanocomposite ، thermal explosion mode