Alloying composition for self-shielded FCAW wires

1. A flux cored welding electrode comprising a ferrous metal sheath and a core within the sheath including core ingredients, the core ingredients comprising, in weight percent based on the total weight of the flux cored welding electrode:

2.0-3.0 aluminum;

1.0-2.0 manganese; and

0.001-0.5 rare earth metal oxide comprising three or more of Cerium (Ce), Lanthanum (La), Neodymium (Nd) and Praseodymium (Pr).

2. The flux cored welding electrode of claim 1 , wherein the rare earth metal of the rare earth metal oxide comprises up to 0.11 wt. % of the total weight of the metal sheath and core ingredients.

3. The flux cored welding electrode of claim 1 , wherein the amount of rare earth metal oxide in weight percent based on the total weight of the flux cored welding electrode is 0.001-0.35.

4. The flux cored welding electrode of claim 1 , wherein the flux cored welding electrode is capable of yielding a weld having a diffusible hydrogen level of 5 ml/100 g or less and a Charpy V-notch toughness at −40° F. of at least 100 ft-lbs.

5. The flux cored welding electrode of claim 1 , wherein the rare earth metal oxide comprises Ce2O3—La2O3—Nd2O3—Pr2O3.

6. The flux cored welding electrode of claim 1 , wherein the core ingredients further comprise, in weight percent, based on the total weight of the flux cored welding electrode:

9.54 of a first sintered fluoride;

4.53 sintered oxide;

0.42 of a second sintered fluoride;

2.04 aluminum;

1.77 magnesium;

1.00 manganese;

0.87 nickel;

0.21 Ce2O3—La2O3—Nd2O3—Pr2O3; and

0.36 iron; or

9.13 of a first sintered fluoride;

4.53 sintered oxide;

0.83 of a second sintered fluoride;

2.10 aluminum;

1.77 magnesium;

1.01 manganese;

0.98 nickel;

0.10 Ce2O3—La2O3—Nd2O3—Pr2O3; and

0.03 iron; or

9.13 BaLiF3;

4.51 Li2O—CaO—SiO2—Fe3O4;

0.42 KLiF2;

2.04 aluminum;

1.77 magnesium;

0.96 manganese;

0.87 nickel;

0.44 zirconium dioxide;

0.07 Ce2O3—La2O3—Nd2O3—Pr2O3; and

0.53 iron.

7. The flux cored welding electrode of claim 6 , wherein the first sintered fluoride comprises BaLiF3, the sintered oxide comprises Li2O—CaO—SiO2—Fe3O4 and the second sintered fluoride comprises KLiF2.

8. A flux composition for a cored welding electrode, the flux composition comprising, in weight percent based on the total weight of the flux cored welding electrode:

2.0-3.0 aluminum;

1.0-2.0 manganese; and

0.001-0.5 rare earth metal oxide comprising three or more of Cerium (Ce), Lanthanum (La), Neodymium (Nd) and Praseodymium (Pr).

9. The flux composition of claim 8 , wherein the amount of rare earth metal oxide in weight percent based on the total weight of the flux cored welding electrode is 0.001-0.35.

10. The flux composition of claim 8 , wherein the rare earth metal oxide comprises Ce2O3—La2O3—Nd2O3—Pr2O3.

11. The flux composition of claim 8 , wherein the composition comprises, in weight percent, based on the total weight of the flux cored welding electrode:

9.54 of a first sintered fluoride;

4.53 sintered oxide;

0.42 of a second sintered fluoride;

2.04 aluminum;

1.77 magnesium;

1.00 manganese;

0.87 nickel;

0.21 Ce2O3—La2O3—Nd2O3—Pr2O3; and

0.36 iron; or

9.13 of a first sintered fluoride;

4.53 sintered oxide;

0.83 of a second sintered fluoride;

2.10 aluminum;

1.77 magnesium;

1.01 manganese;

0.98 nickel;

0.10 Ce2O3—La2O3—Nd2O3—Pr2O3; and

0.03 iron; or

9.13 BaLiF3;

4.51 Li2O—CaO—SiO2—Fe3O4;

0.42 KLiF2;

2.04 aluminum;

1.77 magnesium;

0.96 manganese;

0.87 nickel;

0.44 zirconium dioxide;

0.07 Ce2O3—La2O3—Nd2O3—Pr2O3; and

0.53 iron.

12. The flux composition of claim 11 , wherein the first sintered fluoride comprises BaLiF3, the sintered oxide comprises Li2O—CaO—SiO2—Fe3O4 and the second sintered fluoride comprises KLiF2.