The invention discloses a
defect repair method of a high-temperature
alloy casting, and belongs to the technical field of
precision casting of metallurgical
casting. A defect communicated with the surface of the
casting is changed into a closed defect by using
electron beam surface blocking, and then
hot isostatic pressing is performed on the closed defect, so that the qualification rate of the casting is improved. The
electron beam surface blocking process comprises the following steps and control technical parameters: detecting through
visual contact,
fluorescence and X-
ray to determine a loose region and level;
machining a square or circular groove with an area of being greater than that of the defect and depth of 3-5 mm on the surface with the defect of the casting if a defect beyond tolerance communicated with the surface exists;
machining a matchable cover plate with thickness equal to that of the groove and gap of 0.1-0.5, placing the cover plate on the groove and spot-
welding at 3-4 positions by using
argon arc welding for fixation; sealing and
welding the cover plate at the groove of the casting by using an
electron beam under the condition that the vacuum degree is 10<-4> to 10<-1> Pa. The method has the advantages that the electron beam surface defect blocking and
hot isostatic pressing defect closing are combined, the effectiveness for repair of the casting through the
hot isostatic pressing is improved, and the method can be used for producing high-temperature
alloy composite members.