Synthesis of Cr2AlC Ceramic Powder by Microwave Hybrid Heating

Highly pure Cr2AlC ceramic powders were synthesized by microwave hybrid heating pure Cr, Al and Cr3C2 powders at a temperature between 700 and 1050℃ for 3 min in argon atmosphere. The effects of material ratio and sintering temperature on the resulting Cr2AlC were studied. The phase composition and microstructure of samples were characterized by XRD, SEM and DSC techniques. The results indicated that single phase Cr2AlC in the sample was obtained for composition n (Cr3C2):n(Al):n(Cr)=1:2.0:1. When n(Cr3C2):n(Al):n(Cr)=1:(2.1~2.4):1, single phase Cr2AlC with small amount of graphiteand Cr8Al5 was obtained. The amount of Cr2AlC phase was increased rapidly by the reaction between Cr-Al intermetallic compounds, and un-reacted Cr and Cr3C2 was decreased in the temperature range of 700℃ to 1000℃ by microwave hybrid heating. However, single phase Cr2AlC ceramic powders with an average particle size in the range of 5 μm to 8 μm were achieved at 1050℃ for 3 min. © 2017, Editorial Office of FINE CHEMICALS. All right reserved.