| 摘要 |
PURPOSE:To prevent the initiation of weld crack, by improving intensity by lowering C content in welding wire composition and adding a specific quantity of Ni, Mo, Nb and also, making crystal grain minute by adding Zr, Mg. CONSTITUTION:High intensity maltensitic MIG wire is composed of C;<0.03%, Si; 0.3-1.0%, Mn; 0.6-1.5%, Ni; 3.5-4.5%, Cr; 11.5-13%, Mo; 0.3-1.5%, Mg+Zn; 0.005-0.09% Fe; balance and total quantity of C and Nb is not exceeded 0.15%. The above wire is used for automatic welding of every kind of welded structure made of 13 Cr cast or forging steel. High yield strength and superior impact value are obtained by the wire having the above composition and also, welding is able to carry out at about 100 deg.C of preheating temperature and then, welding quality and workability are improved. |
