US 12,337,420 B2
Multi-coated electrode for welding stainless steel
Sorin Craciun, Buzau (RO)
Assigned to DUCTIL SA, Buzau (RO)
Appl. No. 16/315,117
Filed by DUCTIL SA, Buzau (RO)
PCT Filed Jul. 4, 2017, PCT No. PCT/EP2017/066590
§ 371(c)(1), (2) Date Jan. 3, 2019,
PCT Pub. No. WO2018/007364, PCT Pub. Date Jan. 11, 2018.
Claims priority of application No. 16305846 (EP), filed on Jul. 5, 2016.
Prior Publication US 2019/0308281 A1, Oct. 10, 2019
Int. Cl. B23K 35/02 (2006.01); B23K 35/36 (2006.01); B23K 35/365 (2006.01); B23K 35/40 (2006.01); B23K 103/04 (2006.01)
CPC B23K 35/0272 (2013.01) [B23K 35/3607 (2013.01); B23K 35/3608 (2013.01); B23K 35/365 (2013.01); B23K 35/404 (2013.01); B23K 2103/04 (2018.08)] 21 Claims
 
1. A coated electrode comprising:
a central metal core comprising a stainless steel having chromium alloyed with iron;
an outer coating at least partly surrounding the central metal core, the outer coating comprising rutile and at least one lithium-based compound, wherein the outer coating is essentially free of sodium (Na) feldspar and potassium (K) feldspar; and
at least one inner coating arranged between the outer coating and the central metal core, the inner coating comprising:
rutile,
at least one lithium-based aluminosilicate having lithium (Li) in an amount of 0.1 to 1% by weight on the basis of a total weight of the inner coating,
a lithium silicate, and
one or both of a sodium-based aluminosilicate and a potassium-based aluminosilicate,
wherein about 10 to 55% by weight of the total weight of the inner coating is in the form of ferroalloys or of individual elements,
wherein the outer coating and the inner coating represent between 35% and 42% of the total weight of the electrode.
 
21. An assembly of a central metal core, an inner coating and an outer coating for an electrode, the central metal core comprising a stainless steel having chromium alloyed with iron, the outer coating covering at least a part of the inner coating, the outer coating comprising rutile and at least one lithium-based compound and being free of sodium feldspar and potassium feldspar, wherein the inner coating comprises rutile, at least one lithium-based aluminosilicate, a lithium silicate, and one or both of a sodium-based aluminosilicate and a potassium-based aluminosilicate, wherein the outer coating and the inner coating represent between 35% and 42% of the total weight of the electrode, and wherein the inner coating comprises:
lithium (Li) in the at least one lithium-based aluminosilicate present in an amount of 0.1 to 1% by weight on the basis of a total weight of the inner coating; and
about 10 to 55% by weight of the total weight of the inner coating is in the form of ferroalloys or of individual elements.