| 摘要 |
PURPOSE:To obtain the Ni base covered arc electrode with tension performance and bending performance improved, by limiting the oxygen quantity of the core containing Ni and by specifying the metallic carbonate and moisture quantity in the coating material and by adding specific quantities of B, Al, Ti, and Si. CONSTITUTION:60% or more Ni is contained in the core, and the oxygen quantity is controlled to 0.02% or less. 20-60% Metallic carbonate is contained for all of the weight of the coating material, and the moisture quantity is controlled to 0.5% or less. Further, 0.001-0.01% B as the effective B quantity and 1-7% the total of one or more of Al, Ti, and Si for the weight of the core are mixed with one or both of the core and the coating material. However, effective B quantity=0.5X (B quantity % in the core)+0.15X(the B quantity in B alloy in the coating material)+0.05X(the B quantity in the B compound in the coating material) is true. 0.5% or less the mineral containing moisture is mixed with the coating material as required. By this electrode, fragility of the crystal grain field of the weld metal is prevented. |
