Synthesis of TiB₂/Fe-Cr-Al Nanocomposite Powder

In this study, a route for synthesizing TiB₂/Fe-Cr-Al nanocomposite is proposed via high energy ball milling by using directly coarse powders of TiB₂, Fe, Cr and Al. Various compositions of these powder mixtures are milled up to 48 hrs to investigate the effect of composition on the crystalline refinement. The crystalline size is analyzed by an X-ray diffractometer for powder samples containing 30 to 100 wt% TiB₂ (the rest of the powder consists of Fe-20 wt%Cr-5 wt%Al composition). The crystalline size after 48 hrs of ball milling decreases with increasing TiB₂, and then again increases after reaching a minimum value of 18 nm at 70% TiB₂. By transmission electron microscopic analysis, it is confirmed that particles of TiB₂ are significantly reduced and finely dispersed in the Fe-Cr-Al matrix. The particle size of TiB₂ is found around 20–25 nm, reinforced in the matrix. Considering the results of this study, the proposed mechanical milling route can be recommended as a promising way for fabrication of TiB₂/Fe-Cr-Al nanocomposite powder.