The size distribution of powders(B4C, CaB6 and Al2O3) used in this study was investigated by laser particle analyzer. The D50 were 2.80 μm, 86.00 μm and 3.10 μm, respectively. To get uniform mixed powder, the ball milling was used. The samples listed in Table1 were mixed and milled in the ball mill with 300r/min for18 h. The size distribution of blended powders was investigated by laser particle analyzer. Fig. 1 and Fig. 2 were the macrophoto and size distribution of samples of powders, respectively.