Research Of Fabrication And Properties For In Situ Ferrous Matrix Composites

In situ particulates reinforced metal matrix composites have become one of interesting topics in the field of metal matrix composites(MMCs). The method of in situ accounting to the principle of thermodynamic equilibrium forms reinforcements in the matrix directly. It successfully resolves the problems that wettability is difficult and interface reaction is bad between reinforcements and matrix if the reinforcements are added to the matrix. In order to provide the traditional iron and steel materials powerful activity and meet the higher requirements presented by modern industry development. The text has studied the fabrication and its properties of TiC_p/Fe composites and VC_p/Fe composites by means of the principle of in situ.At first the analyses of thermodynamics indicates that it is feasible for the combination reaction of TiC_p and VC_p. Then, have studied the temperature retention time and alloying element Cu, Ni for response to influence of the organization and properties of TiC_p/Fe composites. The result shows: The longer temperature retention time is , the more TiC_p produced are. And Cu, Ni can consolidate the matrix of composites. Having also studied chemical composition to the influence of organization and properties of VC_p/Fe composites by means of orthogonal design. The result shows: V and C influence the formation of VC_p directly, and also influence the organization and properties of VC_p/Fe composites. Accounting to the mechanical properties , the best chemical content of V and C is: V%_wt=3.5, C%_wt=1.0, Studying the microstructure of VC_p/Fe composites ,we find that VC_P combines with the matrix very well and there is no obvious interface reaction.The text has concentrated on studying the casting properties of TiC_P/Fe composites and VC_P/Fe composites. The result shows: The line shrinking rate ofthese two kinds of composites is smaller than that of ordinary low carbon steel, incline to produce and concentrate on contracting emptily while solidifying, mobility is worse than that of dust casting iron. Their properties are good when they were smelt again, TiC , VC do not have obvious decline phenomenon, so there is very good recovery value.