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In this paper, pressure infiltration method successfully prepared matrix alloy composition of Al-10Mg, Al-13Mg of Al-17.4Mg, Al-17.4Mg 0.2Nd, Al-17.4Mg 0.5Nd, Al-17.4Mg 2Nd fiber volume scores are 55% six Grf / Al composites. By optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), analysis of the balance, Brinell hardness tester, universal electronic tensile testing machine, three-electrode potentiostat analysis test equipment, system The comparative analysis of The six different base body Grf/Al- the composite microstructure, mechanical properties, and its corrosion test. Form of Al-Mg matrix alloy αAl-phase to dendrites grow up, β (Al 3 Mg 2 ) phase in the interdendritic formed as the Mg content increases matrix alloy grain refinement, the β phase increases, an increase in the hardness of the matrix alloy. Nd added, eliminating the dendritic structure, so that the grain refinement, rare earth precipitated phase precipitates in the β phase phase boundary. With the increase of the Nd rare earth precipitation (NdAl 3 ), an increase in the hardness of the matrix alloy reduced increase. The microstructure observations suggest that six different matrix Grf / Al composite tissue is dense, uniform fiber dispersion, no obvious holes, no fiber segregation defects. Transmittance tissue observation: Mg in the interface segregation reduce Al-direct contact with the fiber, thereby reducing the degree of interfacial reaction, as the base body of the Mg content increases, the number of interface brittle phase Al4C3 reduce, β phase precipitates in the fiber interface. Nd reduce the β phase Mg to the diffusion of the α-solid solution, Nd strengthen the segregation of Mg at the interface in the solidification process. With the increase of the Nd rare earth precipitation increased and the rare earth precipitates generated in the fiber interface relative priority, grew up along the fiber longitudinal rare earth precipitated phase reduces the mechanical properties of the composite. When the rare earth precipitate phase coated fiber, completely occupy the fiber gap will significantly reduce the mechanical properties. The hardness and bending performance tests show: M40/Al-Mg three composite material has a hardness value, bending strength, specific strength, elastic modulus, than the elastic modulus with increasing Mg content increased successively. M40/Al-17.4Mg Nd three kinds of changes in the hardness of the composite material and the matrix alloy, the first decreased and then increased with increasing Nd content; flexural strength, to gradually reduce the ratio of the intensity with increasing Nd content. Elastic modulus, Nd change smaller than the elastic modulus, little change. Optimal the six composite M40/Al-17.4Mg mechanical properties. The polarization curves: M40/Al-17.4Mg composite lower corrosion potential, corrosion current density, corrosion rate. Nd-added so that the corrosion potential of the composite material is decreased, but the corrosion current density is decreased, the corrosion rate decreased whole Nd added a corrosive action on the material can affect not great.
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