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Spray deposited SiCP/Al-Fe-V-Si composite is characterized with pores and oxide films between deposited particles, therefore further densification is needed. Densification of the composite preforms in large size has becomes the research emphasis and challenge. Current research of the composite is focused on densification technologies used to eliminate metallurgical defects. Key parameters of wedge pressing, density and stress distribution, flow behaviour, densification mechanism and regularity are investigated by combining experiment and finite element modelling. Pass reduction of 10%~15% and space of about 10mm between one end of the plate blank and the steel mould is beneficial to wedge pressing because of the effective deformation. Density and stress of the external layer are higher than that of the inter layer, density and stress distribution become uniform with overall reduction. Materials in preformed area flows along thickness direction as thickness of the plate decreases, while materials in main deformation area flows along length direction with increasing length of the plate. Wedge pressing of the spray deposited Al matrix composite plate follows porous metal plastic deformation mechanism under the condition of plane strain. Practical relative density of the plate is higher than the calculated value in the initial stage of pressing, while the practical relative density becomes lower than the calculated value as true strain exceeds 0.55, which can be attributed to the pores resulted from aggregation and breaking of SiC particles.

Improving the tribological properties of Inconel 625 is of great significance for its application in slewing bearing and bearing parts of mechanical transmission system in nuclear power plants. In this study, the tribological properties of textured surface (GTSs) and smooth surface (SS-20) of Inconel 625 under different loads during dry sliding friction were researched. The results show that GTSs improves tribological properties of Inconel 625 obviously. The friction coefficient of GTSs is lower than that of SS-20. The grooves on GTSs play a role in capturing wear debris during the friction process, which improve the contact surface characteristics between counterpart ball and substrate, leading to the reduction in wear loss. When the load is 20 N, the Inconel 625 with textured surface has the best tribological performance. The excessive load will cause the big deformation of material and decrease the capacity of capturing wear debris of grooves, resulting in the accumulation of debris and the severe wear of wear track.