Abstract: The forged Fe-11Cr-2.5Mo-1Ni-0.1Zr damping steel plate was welded by TIG homogeneous welding. Take samples from the welded steel plate and conduct heat treatment of heat preservation at 900℃ for 1 h then cooling with furnace in vacuum environment. The damping capacity of the alloy under different prestress were studied by TA Q800dynamic mechanical analyzer. The results show that with the increase of prestress value, the damping property of the alloy decreases, but the decreasing amplitude is small. The mechanical properties of the alloy were studied by universal testing machine and impact testing machine. It is found that the alloy has good mechanical properties after welding, and the strength of the weld is higher than that of the base metal. Through scanning electron microscope, it is observed that due to plastic deformation, there are a lot of fiber structures and dimple structures formed in the impact process on the fracture surface of the impact specimen, which effectively absorbs the impact energy and prevents the spread of cracks. The fracture mode of the alloy is ductile fracture.