CN101362260A - Stainless steel electrode special for magnesium reduction pot - Google Patents

Abstract

The invention relates to a stainless steel welding rod specially used for the reduction pot in the magnesium industry, which belongs to the field of welding material. The welding rod is formed by mixing the following powder raw materials, adding 2.8M and 48 degree Be potassium sodium water glass which is 25 percent of the total weight of the powder raw materials, and uniformly stirring and coating the materials on the stainless steel core welding-wire through extrusion: according to the part by weight, the powder raw materials comprise 43-52 parts of marble, 16-23 parts of fluorspar, 1-3 parts of white titanium pigment, 1-3 parts of quartz, 1-3 parts of mica, 4-6 parts of ferrosilicon, 3-5 parts of ferrotitanium, 4-6 parts of ferromanganese, 8-12 parts of ferrochrome, 1-3 parts of calcium solvent, 1-3 parts of soda ash, and 8-12 parts of nitrided ferro-chromium; according to the mass percent, the core welding-wire comprises the following chemical compositions: smaller than or equal to 0.15 of C, smaller than or equal to 0.35 of Si, 1.0-2.5 of Mn, smaller than or equal to 0.03 of P, smaller than or equal to 0.015 of S, 8.0-10.0 of Ni, 25.0-28.0 of Cr, smaller than or equal to 0.75 of Mo, smaller than or equal to 0.75 of Cu, and residue of Fe. The welding rod has strong oxidation resistance, sulfidation resistance and corrosion resistance, good crack resistance, high welding efficiency, large electric arc blowing force, and good welding performance; during the welding, the electrode coating is uneasy to turn red and crack, the rest part of the welding rod is short, the slag release is easy in a deep and narrow groove, special equipment is not required, and the cost is low.

Description

Stainless steel electrode special for magnesium reduction pot

Technical field

The invention belongs to field of welding material, particularly a kind of refining magnesium industry reduction jar special-purpose stainless steel electrode that is applicable to.

Background technology

Magnesium alloy is the important light metal that is widely used in industry-by-industry at present, and the refinement of metal M g is normally inserted magnesium-containing ore and reducing agent in the reduction jar, and under vacuum state, 1200 ℃ of left and right sides roasting reductions, heat medium are coal or coal gas etc.The welding of magnesium reduction pot before, usually select the welding of A407 or A402 welding rod for use, this weld metal can bear 900～1100 ℃ of high-temperature oxydations, because reduction magnesium tank skin thickness rate is bigger, constraint stress is bigger, the weld seam center is prone to fire check, cause tank body gas leakage or use in end socket come off, tank body was lost efficacy.Simultaneously, refine the technological requirement of Mg: reduction temperature and produces pernicious gas (w in the coal (S) ≈ 0.4%) such as part S during coal combustion generally about 1200 ℃, has quickened the oxidation of weld metal.As mentioned above, because most high chromium nickel (A407) welding rods that adopt of the welding rod of used reduction jar can't reach with mother metal be complementary (table 1 magnesium is already used the stainless steel tank body material, table 2 A407 welding rod deposited metal composition), in welding process, be prone to fire check, yield rate is reduced.

The rise of the simultaneous prices of raw and semifnished materials, especially rising steadily of nickel valency, product cost become the big problem that concerns industry development.Based on this situation, developing a kind of magnesium industry welding rod special for special of magnesium jar welding that is applicable to has become the trend of industry, and has crucial meaning.

Table 1 magnesium is already used stainless cylinder of steel material

C	Si	Cr	Ni	N	S	P
							0.30-0.65	≤ 1.5	25.0-28.0	7.0-9.0	≤ 0.25	≤ 0.03	≤ 0.03

Table 2 A407 welding rod deposited metal composition

C	Mn	Si	S	P	Cr	Ni	Mo	Cu
									0.08-0.20	1.0-2.5	≤ 0.75	≤ 0.03	≤ 0.03	25.0-28.0	20.0-22.5	≤ 0.75	≤ 0.75

Summary of the invention

The object of the present invention is to provide a kind of stainless steel electrode of forming by alloying elements such as Cr, Ni, Mn, to overcome the deficiencies in the prior art.

The invention provides a kind of stainless steel electrode special for magnesium reduction pot, it is characterized in that: it is 2.8M, the 48 ° of Be potassium-sodium water glasses that mixed and added powder raw material gross weight 25% by following powder raw material, stir the stainless steel electrode that extrusion forms on the stainless steel core wire:

Described powder raw material weight portion proportioning: marble 43-52 part; Fluorite 16-23 part; Titanium dioxide 1-3 part; Quartzy 1-3 part; Mica 1-3 part; Ferrosilicon 4-6 part; Ferrotianium 3-5 part; Ferromanganese 4-6 part; Ferrochrome 8-12 part; Calcium solvent 1-3 part; Soda ash 1-3 part; Nitrided ferro-chromium 8-12 part;

The core wire chemical composition mass percent of described stainless steel electrode is as follows: C≤0.15, and Si≤0.35, Mn:1.0-2.5, P≤0.03, S≤0.015, Ni:8.0-10.0, Cr:25.0-28.0, Mo≤0.75, Cu≤0.75, all the other are Fe.

C: an amount of carbon makes weld metal have better heat-resisting.If it is low that carbon content was lower than in deposited metal, the resistance to elevated temperatures variation.If carbon content is greater than 0.2%, then heat-resistant cracking will reduce, the solderability variation.Therefore, carbon content is in the scope of 0.05-0.20%.

S: Sulfur capacity easily causes fire check in welding process, needs strict its content of control, and its content should be in≤0.03% scope.

P: phosphorus also is that fire check is had adverse influence, also needs strict control content, and its content should be≤0.04%.

Cr: add chromium and can well improve weld seam corrosion resistance and heat resistance, can effectively improve weld metal in the anti-burning of high temperature more than 1000 ℃, so the content of chromium should be in the scope of 24.0-28.0%.

N: nitrogen has strong austenitizing effect, improves the resistance to elevated temperatures of weld metal.If but nitrogen content has surpassed 0.25%, will separate out harmful phase of nitrogen, be unfavorable for the heat-resistant cracking energy of weld seam, and can produce pore after the welding, be unfavorable for the sealing of weld seam.Therefore, nitrogen content is in the scope of 0.1-0.25%.

Cu: copper improves corrosion resistance by the hardness and the tensile strength of its precipitation effect increase material.But the copper too high levels causes HOT CRACK FOR WELDING P easily.Therefore, the content of copper should be strict controlled in≤0.75% scope in.

Si: silicon is a kind of strong ferrite former, can improve the resistance to elevated temperatures of weld seam, but the heat resistanceheat resistant crack performance of weld metal is descended, and should control its content, and its content should be in≤1.2% scope.

Mn: manganese equally also is the austenite shaping element, affects the intensity and the toughness of deposited metal.Manganese can limit the illeffects of sulphur, prevents to produce fire check at austenitic weld seam.If manganese content is lower than 1.0% in deposited metal, then the toughness of deposited metal and heat resistanceheat resistant crack performance reduce.If manganese content is higher than 3.0%, then the intensity of weld metal is excessive, causes toughness to reduce.Therefore, manganese content should be in the scope of 1.0-3.0%.

Ni: nickel has the effect of the transition temperature reduction of the brittle fracture of making, and has improved the toughness of deposited metal therefrom.And the adding of nickel helps improving the resistance to elevated temperatures of weld metal.Yet excessive adding nickel causes hot tearing (solidification cracking) easily in weld metal.Therefore, Ni content should be in the scope of 7.0-10.0%.

Mo: can improve the resistance to elevated temperatures of weld metal, but excessive adding Mo can make the transition temperature of brittle fracture transfer to higher temperature, thereby cause the toughness of deposited metal to reduce.Therefore, Mo content is in≤0.75% scope.

The present invention compared with prior art, it makes cost reduction and resistance to oxidation, anti-sulfuration, decay resistance strong, has good crack resistance; The welding efficiency height; Blow force of arc is big, good welding performance; Coating is difficult for rubescent cracking in the welding, and the welding rod remainder is short, saves welding rod, and it is easy to take off slag in dark narrow groove, adopts the manufacturing of current welding rod production technology, need not special equipment, and is with low cost.

The specific embodiment

The present invention is further described below in conjunction with embodiment:

This welding rod is through mixing by the powder raw material of following weight parts proportioning, and 2.8M, 48 ° of Be potassium-sodium water glasses (Beijing waterglass factory) of adding powder raw material gross weight 25%, stir the stainless steel electrode that extrusion forms: marble 43-52 part on H0Cr26Ni9 (according to the national standard name) stainless steel core wire; Fluorite 16-23 part; Titanium dioxide 1-3 part; Quartzy 1-3 part; Mica 1-3 part; Ferrosilicon 4-6 part; Ferrotianium 3-5 part; Ferromanganese 4-6 part; Ferrochrome 8-12 part; Calcium solvent (mineral compound of calcium, composition are 50% calcium carbonate and 50% calcium oxide, are used to improve the extrusion of welding rod, can buy on the market) 1-3 part; Sodium carbonate 1-3 part; Nitrided ferro-chromium 8-12 part.

The used core wire of this welding rod is to adopt H0Cr26Ni9 (according to the national standard name) stainless steel welding stick.The chemical composition of welding wire is as follows: C≤0.15, and Si≤0.35, Mn is 1.0-2.5, P≤0.03, S≤0.015, Ni is 8.0-10.0, Cr is 25.0-28.0, Mo≤0.75, Cu≤0.75 is called H0Cr26Ni9 (according to the national standard name).This core wire adds high temperature oxidation resisting, alloying component such as anticorrosive in fusion process.The welding rod of Zhi Zaoing is compared with high chromium-nickel electrode on this basis, can improve the weld seam cracking resistance, reduces cost, and guarantees the high temperature endurance performance of weld metal, thereby prolong the service life of reduction jar.Adopt welding rod welding magnesium reduction pot of the present invention, welding condition is: welding current 140-200A, and weldingvoltage is 26-35V, the postwelding deposited metal composition scope that obtains is as follows, sees Table 3.

Table 3 welding rod welding deposited metal composition scope

C	Mn	Si	S	P	Cr	Ni	N	Mo	Cu
										0.0 5 - 0.2	1.0 - 3.0	≤ 1. 2	≤0. 03	≤0. 04	24.0 28.0	7.0 - 10. 0	0.1 - 0.2 5	≤0. 75	≤0. 75

Embodiment 1, get marble 43kg, fluorite 16kg, titanium dioxide 1kg, quartzy 1kg, mica 1kg, ferrosilicon 4kg, ferrotianium 5kg, ferromanganese 6kg, ferrochrome 8kg, calcium solvent 1kg, sodium carbonate 3kg, the powder of nitrided ferro-chromium 8kg mixes, 2.8M with 24.25kg, mix in 48 ° of Be potassium-sodium water glasses adding dry powder, with the hydraulic press extrusion on H0Cr26Ni9 stainless steel core wire, the chemical composition of stainless steel core wire is: C:0.1, Si:0.25, Mn:2.0, P:0.02, S:0.008, Ni:9.0, Cr:27, Mo:0.1, Cu:0.1, welding rod dried naturally through 24 hours, and hyperthermia drying forms then.Welding rod welding back deposited metal composition is: C:0.1, Mn:2.11, Si:0.67, S:0.009, P:0.031, Cr:26.63, Ni:7.72, N:0.19, Mo:0.08, Cu:0.13, the life cycle of postwelding reduction jar can reach 80 days (prior art is 40 days).

Embodiment 2, get marble 52kg, fluorite 23kg, titanium dioxide 3kg, quartzy 3kg, mica 3kg, ferrosilicon 6kg, ferrotianium 3kg, ferromanganese 4kg, ferrochrome 12kg, calcium solvent 3kg, sodium carbonate 1kg, the powder of nitrided ferro-chromium 12kg mixes, 2.8M with 31.25kg, mix in 48 ° of Be potassium-sodium water glasses adding dry powder, with the hydraulic press extrusion on H0Cr26Ni9 stainless steel core wire, the chemical composition of stainless steel core wire is: C:0.1, Si:0.25, Mn:2.0, P:0.02, S:0.008, Ni:9.0, Cr:27, Mo:0.1, Cu:0.1, welding rod dried naturally through 24 hours, and hyperthermia drying forms then.Welding rod welding back deposited metal composition is: C:0.1, Mn:2.05, Si:0.7, S:0.009, P:0.031, Cr:26.9, Ni:7.72, N:0.21, Mo:0.08, Cu:0.13, the life cycle of postwelding reduction jar can reach 82 days (prior art is 40 days).

Embodiment 3, get marble 50kg, fluorite 22kg, titanium dioxide 2kg, quartzy 3kg, mica 3kg, ferrosilicon 5kg, ferrotianium 3kg, ferromanganese 4kg, ferrochrome 11kg, calcium solvent 2kg, sodium carbonate 1kg, the powder of nitrided ferro-chromium 10kg mixes, 2.8M with 29kg, mix in 48 ° of Be potassium-sodium water glasses adding dry powder, with the hydraulic press extrusion on H0Cr26Ni9 stainless steel core wire, the chemical composition of stainless steel core wire is: C:0.1, Si:0.25, Mn:2.0, P:0.02, S:0.008, Ni:9.0, Cr:27, Mo:0.1, Cu:0.1, welding rod dried naturally through 24 hours, and hyperthermia drying forms then.Welding rod welding back deposited metal composition is: C:0.1, Mn:2.05, Si:0.67, S:0.009, P:0.031, Cr:26.88, Ni:7.72, N:0.2, Mo:0.08, Cu:0.13, the life cycle of postwelding reduction jar can reach 80 days (prior art is 40 days).

Embodiment 4, get marble 51kg, fluorite 23kg, titanium dioxide 1kg, quartzy 2kg, mica 2kg, ferrosilicon 6kg, ferrotianium 4kg, ferromanganese 5kg, ferrochrome 12kg, calcium solvent 2kg, sodium carbonate 2kg, the powder of nitrided ferro-chromium 11kg mixes, 2.8M with 30.25kg, mix in 48 ° of Be potassium-sodium water glasses adding dry powder, with the hydraulic press extrusion on H0Cr26Ni9 stainless steel core wire, the chemical composition of stainless steel core wire is: C:0.1, Si:0.25, Mn:2.0, P:0.02, S:0.008, Ni:9.0, Cr:27, Mo:0.1, Cu:0.1, welding rod dried naturally through 24 hours, and hyperthermia drying forms then.Welding rod welding back deposited metal composition is: C:0.1, Mn:2.11, Si:0.68, S:0.009, P:0.031, Cr:27, Ni:7.72, N:0.2, Mo:0.08, Cu:0.13, the life cycle of postwelding reduction jar can reach 81 days (prior art is 40 days).

Embodiment 5, get marble 52kg, fluorite 23kg, titanium dioxide 3kg, quartzy 3kg, mica 3kg, ferrosilicon 6kg, ferrotianium 3kg, ferromanganese 4kg, ferrochrome 12kg, calcium solvent 3kg, sodium carbonate 1kg, the powder of nitrided ferro-chromium 12kg mixes, 2.8M with 31.25kg, mix in 48 ° of Be potassium-sodium water glasses adding dry powder, with the hydraulic press extrusion on H0Cr26Ni9 stainless steel core wire, the chemical composition of stainless steel core wire is: C:0.1, Si:0.25, Mn:2.0, P:0.02, S:0.008, Ni:9.0, Cr:27, Mo:0.1, Cu:0.1, welding rod dried naturally through 24 hours, and hyperthermia drying forms then.Welding rod welding back deposited metal composition is: C:0.1, Mn:2.05, Si:0.69, S:0.009, P:0.031, Cr:27, Ni:7.72, N:0.21, Mo:0.08, Cu:0.13, the life cycle of postwelding reduction jar can reach 85 days (prior art is 40 days).

Claims (1)

1, a kind of stainless steel electrode special for magnesium reduction pot is characterized in that: it is 2.8M, the 48 ° of Be potassium-sodium water glasses that mixed and added powder raw material gross weight 25% by following powder raw material, stirs the stainless steel electrode that extrusion forms on the stainless steel core wire:

Described powder raw material weight portion proportioning: marble 43-52 part; Fluorite 16-23 part; Titanium dioxide 1-3 part; Quartzy 1-3 part; Mica 1-3 part; Ferrosilicon 4-6 part; Ferrotianium 3-5 part; Ferromanganese 4-6 part; Ferrochrome 8-12 part; Calcium solvent 1-3 part; Soda ash 1-3 part; Nitrided ferro-chromium 8-12 part;

The core wire chemical composition mass percent of described stainless steel electrode is as follows: C≤0.15, and Si≤0.35, Mn:1.0-2.5, P≤0.03, S≤0.015, Ni:8.0-10.0, Cr:25.0-28.0, Mo≤0.75, Cu≤0.75, all the other are Fe.