In order to study the behaviors and characteristics of the superalloy under the multiple deposition technology,an epitaxial deposition was successfully proceeded on a directional solidification（D.S.） substrate by laser cladding ＋ electrospark deposition（ESD）.The optical microscope（OM） and scanning electron microscope（SEM） were employed for investigating the microstructural characteristics of the epitaxial zone on the cross-section.The research results show that the epitaxial deposition zones are uniform and continuous with no obvious defect or flaw,the growth directions are perpendicular to the interfaces and keep consistent to the D.S.substrate.The width of D.S.columnar structures were shown in a gradient descending from D.S.substrate（～300 μm） to ESD zone（～1 μm）.Further analysis shows that the solidification velocity R,temperature gradient G and direction of heat flow on liquid-solid interfaces are the key factors to determine what kind of microstructures can be obtained.
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