The effects of SiCp surface modifications(Cu coating,Ni coating and Ni/Cu coating)on the microstructures and mechanical properties of Al matrix composites were investigated.Surface modification of SiC particles with C...The effects of SiCp surface modifications(Cu coating,Ni coating and Ni/Cu coating)on the microstructures and mechanical properties of Al matrix composites were investigated.Surface modification of SiC particles with Cu,Ni and Cu/Ni,respectively,was carried out by electroless plating method.SiCp/Al composites were prepared by hot pressed sintering followed by hot extrusion.The results show that the surface modification of SiC particles plays an effective role,which is relative to the type of surface coating,and the interfacial bonding become stronger in the following order:untreated SiCp<Ni(Cu)-coated SiCp<Ni/Cu-coated SiCp.The Ni/Cu-coated SiCp/Al composites exhibit the best comprehensive mechanical properties,with ultimate tensile strength(σUTS)and fracture strain(εf)of 389 MPa and 6.3%,respectively.Compared with that of untreated-SiCp/Al composites,theσUTS andεf are enhanced by 19.3%and 57.5%.展开更多
The reactive process for Al/SiC P composite was studied. SiC particles were in situ coated by the exothermal reaction of SiC Ti powder compact in Al melt bath, and easily incorporated into Al melt. The detailed study ...The reactive process for Al/SiC P composite was studied. SiC particles were in situ coated by the exothermal reaction of SiC Ti powder compact in Al melt bath, and easily incorporated into Al melt. The detailed study was carried out to understand the microstructures of the reacted SiC particles. During the reaction and consequent mixing, the successive processes include in situ coating on the reacted SiC particles, coat dissolution and SiC P splitting. The tensile mechanical properties of 6013Al/SiC P composite processed by the present technology showed that the reacted SiC P considerably reinforced the 6013 matrix.展开更多
In order to choose the appropriate reference surface on the machined surface roughness of Si Cp/Al composites, the cutting experiments of Si Cp/Al composites were carried out, and the machined surface topography was m...In order to choose the appropriate reference surface on the machined surface roughness of Si Cp/Al composites, the cutting experiments of Si Cp/Al composites were carried out, and the machined surface topography was measured by OLS3000 Confocal laser scanning microscope. The 3D measured data of machined surface topography were analyzed by the area power spectrum density. The result shows that the texture of machined surface topography in milling of Si Cp/Al composites is almost isotropic. This is the reason that the values of Rq at different locations on the same machined surface are obviously different. Through the comparison of performance of different filtering methods, the robust least squares reference surface can be used to extract the surface roughness of SiC p/Al composites effectively.展开更多
Based on tensile cracking of SiC_p and decohesion of the interface between SiC_p and Al matrix, a mesomechanical model for tensile deformation of SiC_p/Al composites was developed. The microcracks and multi-scale seco...Based on tensile cracking of SiC_p and decohesion of the interface between SiC_p and Al matrix, a mesomechanical model for tensile deformation of SiC_p/Al composites was developed. The microcracks and multi-scale second phase particles were assumed to distribute homogeneously. A nonlinear quantitative relationship between tensile ductility and volume fraction of SiC_p was established based on the model. The tensile ductility values of 2xxx SiC_p/Al and 6xxx SiC_p/Al composites predicted by the model are in good agreement with the experimental values. The analysis of effects of multi-scale second phases on the ductility of the composites indicates that the ductility decreases with the increase of the volume fraction of SiC_p and precipitates in Al matrix and is almost independent of constituents and dispersoids.展开更多
基金Project(2017zzts111)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The effects of SiCp surface modifications(Cu coating,Ni coating and Ni/Cu coating)on the microstructures and mechanical properties of Al matrix composites were investigated.Surface modification of SiC particles with Cu,Ni and Cu/Ni,respectively,was carried out by electroless plating method.SiCp/Al composites were prepared by hot pressed sintering followed by hot extrusion.The results show that the surface modification of SiC particles plays an effective role,which is relative to the type of surface coating,and the interfacial bonding become stronger in the following order:untreated SiCp<Ni(Cu)-coated SiCp<Ni/Cu-coated SiCp.The Ni/Cu-coated SiCp/Al composites exhibit the best comprehensive mechanical properties,with ultimate tensile strength(σUTS)and fracture strain(εf)of 389 MPa and 6.3%,respectively.Compared with that of untreated-SiCp/Al composites,theσUTS andεf are enhanced by 19.3%and 57.5%.
文摘The reactive process for Al/SiC P composite was studied. SiC particles were in situ coated by the exothermal reaction of SiC Ti powder compact in Al melt bath, and easily incorporated into Al melt. The detailed study was carried out to understand the microstructures of the reacted SiC particles. During the reaction and consequent mixing, the successive processes include in situ coating on the reacted SiC particles, coat dissolution and SiC P splitting. The tensile mechanical properties of 6013Al/SiC P composite processed by the present technology showed that the reacted SiC P considerably reinforced the 6013 matrix.
基金Projects(51305284,61203208) supported by the National Natural Science Foundation of China
文摘In order to choose the appropriate reference surface on the machined surface roughness of Si Cp/Al composites, the cutting experiments of Si Cp/Al composites were carried out, and the machined surface topography was measured by OLS3000 Confocal laser scanning microscope. The 3D measured data of machined surface topography were analyzed by the area power spectrum density. The result shows that the texture of machined surface topography in milling of Si Cp/Al composites is almost isotropic. This is the reason that the values of Rq at different locations on the same machined surface are obviously different. Through the comparison of performance of different filtering methods, the robust least squares reference surface can be used to extract the surface roughness of SiC p/Al composites effectively.
基金Project(2005CB623704) supported bythe National Basic Research Programof China Project(NCET-04-0753) supportedby the New Century Talented Professionals Programof Chinese Education Ministry
文摘Based on tensile cracking of SiC_p and decohesion of the interface between SiC_p and Al matrix, a mesomechanical model for tensile deformation of SiC_p/Al composites was developed. The microcracks and multi-scale second phase particles were assumed to distribute homogeneously. A nonlinear quantitative relationship between tensile ductility and volume fraction of SiC_p was established based on the model. The tensile ductility values of 2xxx SiC_p/Al and 6xxx SiC_p/Al composites predicted by the model are in good agreement with the experimental values. The analysis of effects of multi-scale second phases on the ductility of the composites indicates that the ductility decreases with the increase of the volume fraction of SiC_p and precipitates in Al matrix and is almost independent of constituents and dispersoids.
