| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent occurrence of surface crack due to the bond martensite on an outer surface side of a low-alloy steel-made tube. <P>SOLUTION: The structure of a different material joint includes: a cladded-by-welding part 7 provided on a fore end of a low-alloy steel-made tube 2 and consisting of a nickel-based alloy; a boundary weld part 8 provided so as to cover an outer surface of a boundary part between the cladded-by-welding part 7 and the fore end of the low-alloy steel-made tube 2, and consisting of a nickel-based alloy; and a welded part 9 provided between the cladded-by-welding part 7 and an end of a stainless steel-made tube 3 and consisting of a nickel-based alloy. The nickel-based alloy forming the cladded-by-welding part 7 and the weld part 9 contains more chromium and less nickel than the nickel-based alloy forming the boundary weld part 8, and its sensitivity of the stress corrosion crack is low. The nickel-based alloy forming the boundary weld part 8 contains more nickel and less chromium than the nickel-based alloy forming the cladded-by-welding part 7 and the weld part 9, and its sensitivity of generating the bond martensitic structure is low. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
