Mechanical synthesis and rapid consolidation of a nanocrystalline 5.33Fe0.37Cr0.16Al0.4Si0.07-Al2O3 composite by high-frequency induction heating

Nanopowders of 5.33Fe(0.37)Cr(0.16)Al(0.4)Si(0.07) and Al2O3 were synthesized from Fe2O3, Cr, Si, and Al powders by high-energy ball milling. A high-density nanocrystalline 5.33Fe(0.37)Cr(0.16)Al(0.4)Si(0.07)-Al2O3 composite was consolidated by a high-frequency, induction-heated sintering (HFIHS) method within three minutes from mechanically synthesized powders of Al2O3 and 5.33Fe(0.37)Cr(0.16)Al(0.4)Si(0.07). The advantage of this process is that it allows very quick densification to near theoretical density and prohibits grain growth in nano-structured materials. The average grain sizes of Al2O3 and 5.33Fe(0.37)Cr(0.16)Al(0.4)Si(0.07) were 99 nm and 14 nm, respectively. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.