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MoSi 2 and rare earths/MoSi 2 materials were prepared by mechanical alloying, IP and high temperature sintering techniques. Their room temperature properties such as bending strength, fracture toughness and electric conductivity were measured. The results show that rare earths have better strengthening and toughening effects on the MoSi 2 matrix than SiC does. The room temperature bending strength and fracture toughness of 0 9% rare earths/MoSi 2 material are 419 41 MPa and 5 81 MPa·m 1/2 , which have increased by 46% and 81% than the matrix, respectively. The strengthening mechanisms of rare earths/MoSi 2 are fine grain and dispersion strengthening. The toughening mechanisms are fine grain toughening, crack deflection and bowing toughening. Moreover, the effect of rare earths on the electric conductivity of MoSi 2 is much weaker than that of SiC whiskers. With the addition of 0 9% rare earths, the resistivity of MoSi 2 is only raised by about 13 9%.
MoSi 2 and rare earths / MoSi 2 materials were prepared by mechanical alloying, IP and high temperature sintering techniques. Their room temperature properties such as bending strength, fracture toughness and electric conductivity were measured. The results show that rare earths have better strengthening and toughening effects on the MoSi 2 matrix than SiC does. The room temperature bending strength and fracture toughness of 0 9% rare earths / MoSi 2 materials are 419 41 MPa and 5 81 MPa · m 1/2, which have increased by 46% and 81 % of the matrix, respectively. The strengthening mechanisms of rare earths / MoSi 2 are fine grain and dispersion strengthening. The toughening mechanisms are fine grain toughening, crack deflection and bowing toughening. Moreover, the effect of rare earths on the electric conductivity of MoSi With the addition of 0 9% rare earths, the resistivity of MoSi 2 is only raised by about 13 9%.