Effect Of Technological Parameters On Microstructure Of SiC Particulate Reinforced High Manganese Steel Matrix Composite With Process Of V-EPC

In order to improve the wear resistance of steel,and develop the particle reinforced steel matrix composite prepare technology with simple process and low cost, we choose the SiC particiate reinforced high manganese steel matrix composite prepared by process of V-EPC.We studied the microstructure of the composites in different conditions,and the relationship between the microstructure and the casting practice.The results indicated:First,there is a reaction of SiC particle with Fe when casting.The Si atoms diffused into the high manganese steel matrix and formed the solid solution alloy.The active C atom would diffuse into the matrix,too.That would lead to the precipitation of carbides or graphite microstructure.Secondly,the decomposition of SiC particles might be effectively inhibited under low pouring temperature or at faster cooling rate,and the far from the particles the less the carbides in the matrix.When the temperature increased or the cooling rate was decreased,the microstructure characteristics were:SiC particles decomposed completely,recarburization of steel obviously increased.This indicated that,the decomposition of SiC particle was sensitive to temperature.We can avoid the decomposition in some extend by control of temperature and cooling rate.Third,in view of the thermodynamic,the decomposition of SiC particles need enough thermodynamic driving force.And the reaction of Si atom with Fe atom would provide enough energy.As the pouring temperature increased the thermodynamic driving force increased.Fourth,in view of the kinetic,as the pouring temperature increased,the steel viscosity would be lower,the flow velocity of steel would be faster,and the molten steel would keep liquid state for longer,and all these were benefit for the compound. Moreover,the high temperature was benefit to diffusion,the inner layer of the particle would be decomposed.That led to the entire decomposition of the SiC particle.Last of all,as compared with the microstructure of different matrix,it indicated that,the high manganese steel matrix was better than the other matrix in obtaining better composite microstructure.The higher Mn and C contain in the high manganese steel can hinder the decomposition obviously.And the high manganese steel matrix which has good plasticity and toughness,can surport the particles better.The comprehensive properties would be better.