The As-cast Microstructure of ESR-CDS M2 High Speed Steel

The ESR and ESR-CDS casting microstructure of the M2 high speed steel was studied.The results show that the casting' edge is dendrite and appears three times dendrite with ESR,and the structure of heart are coarse equiaxed grains,between which is network carbide,and the segregation of ingot is more serious,the matrix and carbide transition region is loose and rough,and the fine crack is found of some part of the substrate with the deep etching.However,the structure of casting'edge and heart are small dentrite,and there are more "discontinuous composite regular type"carbide,the structure is more uniform,the transition zone of carbide and matrix is smooth with the depth of corrosion.