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Refractory metal silicide Mo 5 Si 3 is considered to be great potential for high-temperature structural candidate material. However, the room temperature brittleness, high temperature strength is insufficient impede its practical application. MoO 3 , Cu, Mo, Si and Al powder as raw material, the use of mechanical activation / hot pressing sintering technology to prepare a Cu-Al 2 O 3 < / sub> / Mo 5 Si 3 -situ composites using XRD, OM, SEM and EDS analysis method of composite material phase composition, microstructure and micro component analysis by electrochemical and soaking experiments to investigate the corrosion of the sample process and the corrosion mechanism, as a corrosion-resistant material for the Mo 5 Si 3 yl composites The application provides a preliminary theoretical basis. Experimental prepared Cu-Al the 2 O 3 / Mo 5 Si 3 composite sample phase Cu, Al 2 the the O 3 and Mo 5 the Si 3 Cu and Al O 3 matrix material Mo 5 Si 3 has good stability. 20% Cu-20% Al 2 O 3 / Mo 5 Si 3 composites have smaller crystal particle size of Mo 5 3 , Mo 5 Si 3 , Al 2 O 3 and Cu grain size were 73.6nm, 66.3nm, 64.8nm and 42.6nm, composite materials with nanocrystalline structure. Uniform and dense hot pressed sintering of Cu-20% Al2O3/Mo 5 Si 3 composite organization. With increasing Cu content in the composite microstructure refinement, sintered density increase, lower microhardness, fracture toughness, strength first increases and then decreases. 15% Cu-20% Al 2 O 3 / Mo 5 Si 3 composite material has the best overall mechanical properties, microhardness, compressive and flexural strength and fracture toughness were 1090HV 2160MPa, 512MPa and 7.33MPa · m1 / 2. H2SO4 and HCl solution, Cu-Al 2 O 3 / Mo 5 Si 3 composites exhibit compared with 304 stainless steel excellent in corrosion resistance, having a high corrosion potential and corrosion current low, and the increase of the content of Cu to improve the corrosion resistance, the corrosion weight loss than 304 stainless steel is almost 30 times lower. NaOH solution, Composites poor corrosion resistance of 304 stainless steel. Al 2 O 3 has good resistance to H 2 SO 4 and HCl solution corrosive composite corrosion surface is easy to form Al 2 O 3 -SiO 2 composite protective layer to prevent corrosion solution further erosion of the matrix. In NaOH solution, since the solution of NaOH dissolved erosion of the surface of the composite material, the passivation film of SiO2, it is difficult to form an effective protective layer, resulting in poor corrosion resistance of composite materials. Cu-Al 2 O 3 / Mo 5 Si 3 composites, Cu to corrosive elements , poor chemical stability and corrosion resistance, so that the composite material. The other hand, the presence of Cu improves the sintering properties of the composite material, to improve the density and reduce the porosity and the presence of microscopic defects and effectively avoid the formation of local galvanic cells, to improve the corrosion resistance.
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