Abstract: The microstructure of solid diffusion welded joint between a new type damping CuAlBe alloy to be used for naval ship propelling screw manufacturing and 1Cr18Ni9Ti stainless steel with Ni foil interlayer was analyzed by means of SEM,EPMA line scan,X-ray diffraction and micro area EDS techniques.The result showed that the microstructure of CuAlBe alloy nearby interface was coarse β phase following a network α phase distributing in grain boundary through thermal cycle.This would cause degeneration of damping function produced by thermal elastic martensite.At the same time,the difference of plastic deforming ability between CuAlBe and 1Cr18Ni9Ti and the Kirkendall effect on Cu-Ni interface would affect atom diffusion at the initial period of diffusion bonding.Moreover,this would influence metallurgy weldability at steady diffusing stage.Otherwise,the diffusion of atoms in welding process exerted some influence on fracture character of material in certain degree.