CN102233489B - Two-phase stainless steel electrode - Google Patents

Abstract

The invention discloses a two-phase stainless steel electrode, which comprises a core wire and a coating, wherein the coating is coated on the outer wall of the core wire and accounts for 0.4 to 0.5 percent of the total weight of the electrode. The core wire comprises the following components in percentage by weight: 0.005 to 0.030 percent of C, 0.01 to 0.20 percent of Si, 1.50 to 2.50 percent of Mn, 0 to 0.025 percent of P, 19.0 to 22.0 percent of Cr, 9.0 to 11.0 percent of Ni, 2.5 to 3.5 percent of Mo and the balance of Fe. The coating comprises the following components in percentage by weight: 8 to 20 percent of calcium carbonate, 2 to 15 percent of barium carbonate, 5 to 15 percent of calcium fluoride, 6 to 17 percent of strontium fluoride, 4 to 16 percent of barium fluoride, 9 to 18 percent of cryolite, 4 to 10 percent of rutile, 1 to 5 percent of titanium white, 2 to 8 percent of silicon dioxide, 3 to 9 percent of chromium powder, 1 to 1.5 percent of molybdenum powder, 0.1 to 4 percent of magnesium powder and 5 to 13 percent of iron powder. After the coating components are uniformly mixed, an adhesion agent is added into the mixture. The two-phase stainless steel electrode has high strength, high tenacity and intercrystalline corrosion resistance; and during welding, an electric arc is stable, splashing phenomena is reduced, a welding seam is well molded, slag is easy to remove, and the electrode has high operability.

Description

Diphasic stainless steel electrode

Technical field

The present invention relates to field of welding material, particularly a kind of diphasic stainless steel electrode.

Background technology

The two-phase stainless hardness of steel is high, and corrosion resistance is good, and especially therefore excellent performance aspect anti-chloride stress cracking corrosivity and pitting corrosion resistance has been widely used in anti-corrosion pressure vessel, pipeline, large-scale chemical tanker etc.At present; Also extensive use two phase stainless steel in China's engineering construction; But supporting with it two phase stainless steel wlding performance is still stable inadequately, and its low-temperature impact toughness can not be satisfied the demand, and especially the intercrystalline corrosion problem under the sensitization treatment conditions often is difficult to solve.

Summary of the invention

In order to overcome above-mentioned defective, the present invention provides a kind of diphasic stainless steel electrode, has high strength, high tenacity and resistance to intergranular corrosion.

The present invention for the technical scheme that solves its technical problem and adopt is:

A kind of diphasic stainless steel electrode comprises core wire and coating, and coating is coated on the core wire outer wall, and the weight coefficient that said coating accounts for the welding rod gross weight is 0.4～0.5, is benchmark with the core wire gross weight, percentage meter by weight, and the component of said core wire is following:

C：0.005～0.030％；

Si：0.01～0.20％；

Mn：1.50～2.50％；

P：0～0.025％；

Cr：19.0～22.0％；

Ni：9.0～11.0％；

Mo：2.5～3.5％；

Fe: surplus;

With the coating gross weight is benchmark, percentage meter by weight, and the component of said coating is following:

Calcium carbonate: 8～20%;

Brium carbonate: 2～15%;

Calcirm-fluoride: 5～15%;

Strontium fluoride: 6～17%;

Barium fluoride: 4～16%;

Ice crystal: 9～18%;

Rutile: 4～10%;

Titanium white powder: 1～5%;

Silica: 2～8%;

Chromium powder: 3～9%;

Molybdenum powder: 1～1.5%;

Magnesium powder: 0.1～4%;

Iron powder: 5～13%;

The component of said coating mixes the back and adds binding agent.

As further improvement of the present invention, said binding agent is a potassium-sodium water glass.

Specifically following to physico-chemical analysis of the present invention:

In the welding rod carbonate mainly act as slag making and gas making, when carbonate content was low, the gas making of coating descended with slaggability, the protective effect reduction of butt welded seam causes the decline of weld properties; If the too high levels of carbonate, coating gas making amount is excessive, and arc stability descends, the increase of splashing, and the welding slag fusing point raises, and appearance of weld is coarse, so the content of carbonate is controlled at 10～35% among the present invention;

Fluoride is a slag former, and the fusing point of scalable slag is because the alloy content of the weld metal of welding rod of the present invention is high; The surface tension of liquid metal is big, and is mobile poor, the appearance of weld variation; Gas is difficult for overflowing in the weld seam, adds a certain amount of fluoride, can reduce the surface tension of liquid metal; Improve its flowability, make appearance of weld attractive in appearance, reduce the defective that weld seam forms pore; Content of fluoride is low, can make that appearance of weld is bad, is prone to venthole in the weld seam, and the fluorite too high levels is destroyed arc stability easily, makes the usability of electrode variation; So the content of fluoride is 20～50% in the welding rod of the present invention;

Rutile makes welding arc stablility, and the molten bath is tranquil, but refinement transition molten drop beautifies appearance of weld, guarantees the slag spreadability, but excessive use makes mechanical performance descend easily, so its content is controlled at 4～10%;

Titanium white powder can increase electrode coating plasticity, is slag former, but improves processing performance not as rutile, and its content is controlled at 1～4%;

But the silica slag making, the spreadability of regulating slag, but excessive meeting reduces mechanical property, and its content is controlled at 2～8%;

The magnesium powder can reduce the oxygen content in the weld seam;

The main effect of chromium powder, molybdenum-iron is the transition alloy, guarantees alloy element component in the weld seam, guarantees that the corrosion resistance of weld seam improves weld strength simultaneously;

The adding of iron powder can be quickened the burn-off rate of coating, improves deposition efficiency, because the employing of this prescription is special basic slag system, so can improve arc stability simultaneously, produces difficulty but cross to make at most, and its content is controlled at 5-13%;

Binding agent adopts potassium-sodium water glass, can play the effect of stabilising arc.

Welding rod of the present invention is arc stability when welding, and it is few to splash, and appearance of weld is good, and it is easy to take off slag, and the welding rod operating characteristics is excellent; The present invention accurately controls alloying component, guarantees the seam organization ratio, and after the technology welding in strict accordance with regulation, through metallographic observation, ferritic content is 40-50% in the seam organization, organizes ratio to satisfy the practical applications requirement; Weld seam has excellent mechanical property, and tensile strength can reach 800MPa, and percentage elongation reaches 28%, and-40 ℃ of low-temperature impacts reach 75J; And weld seam not only has good anticorrosion stress-resistant property, pitting resistance, and intergranular corrosion resistance property is good under the sensitization treatment conditions simultaneously.

The invention has the beneficial effects as follows: in sum, the present invention has high strength, high tenacity and resistance to intergranular corrosion, arc stability when welding, and it is few to splash, and appearance of weld is good, and it is easy to take off slag, and the welding rod operating characteristics is excellent.

The specific embodiment

The present invention includes core wire and coating, its core wire component such as following table (percentage by weight %):

C	Si	Mn	P	S
					0.005-0.03	0.01-0.2	1.5-2.5	0-0.025	0-0.025
Cr	Ni	Mo	Fe
					19-22	9-11	2.5-3.5	Surplus

Its coating component such as following table (percentage by weight %):

CaCO 3	SrF 2	CaF 2	Ice crystal	BaF 2	BaCO 3	Titanium white powder
							8-20	6-17	5-15	9-18	4-16	2-15	1-5
Rutile	Silica	Chromium powder	Molybdenum powder	Iron powder	The magnesium powder
							4-10	2-8	3-9	1-1.5	5-13	0.1-4

It is core wire that the present invention adopts the two-phase stainless steel wire, uses general hand welding rod to make production technology and makes, and the weight coefficient of coating is 0.4-0.5; Core line diameter is 2.6mm, 3.2mm, 4.0mm or 5.0mm; In order to understand the present invention better, further specify through embodiment 1-4 below: each embodiment compositions of surfacing metal (percentage by weight) is as shown in table 1, and each embodiment is actual, and to record core wire composition (percentage by weight) as shown in table 2; After above-mentioned welding rod supports; According to the condition of table 3, weld, the result that each embodiment butt welded seam mechanical property is measured is as shown in table 4; It is as shown in table 5 that the molten golden composition of each embodiment is analyzed summary, but the present invention is not limited to following embodiment:

Table 1: the compositions of surfacing metal of each embodiment (percentage by weight %)

Table 2 core wire component list (percentage by weight %)

Table 3 welding condition

Welding rod line footpath

Welding base metal

The welding position

The mother metal specification

Welding manner

The road temperature

Electric current/translational speed

4.0mm

SUS-2209

F (downhand welding)

300mm×150mm ×20mm

Butt joint

≤150℃

155A/4.2mm·sce -1

The deposited metal mechanical property of table 4: embodiment

Table 5 melts golden component list (percentage by weight %)

Test specimen	C	Si	Mn	P	S	Ni	Cr	Cu	N	Mo	Fe	Pre
													Embodiment 1	0.034	0.53	1.16	0.007	0.0015	8.85	22.87	0.01	0.13	3.00	63.4	34.7
Embodiment 2	0.030	0.46	1.10	0.012	0.011	8.82	23.00	0.02	0.15	3.21	63.1	35.8
													Embodiment 3	0.035	0.46	1.07	0.014	0.008	8.92	23.35	0.02	0.12	3.17	62.8	35.6
Embodiment 4	0.032	0.48	1.15	0.010	0.012	8.85	23.00	0.01	0.14	3.20	63.2	35.8

Pre represents the spot corrosion index in the last table, and its computing formula is following:

Pre＝％Cr+3.3×％Mo+16×％N

Butt welded seam carries out sensitization to be handled, and specification of heat treatment is following:

A, room temperature → 400 ℃, 1 hour heating-up time.

B, 400 ℃ → 675 ℃, 1 hour heating-up time.

C, 675 ℃ the insulation 1 hour.

D, turn off the power supply of annealing furnace, open fire door, the cooling test plate (panel).

After sensitization was handled, the intercrystalline corrosion experiment was undertaken by GB/T4334.5-2000 (stainless steel sulfuric acid-copper sulphate corrosion test method), crackle do not occur after weld seam process sensitization processing, the intercrystalline corrosion, explained that wlding has stronger anti intercrystalline corrosion ability.

Welding is carried out according to standard in the table 2, and butt welded seam is organized corrosion experiment to according to the GB/T13305-2008 standard to carry out, and metallograph shows that the welding bead ferrite content is between 40%-50%.

Adopt welding rod of the present invention to weld; Weld seam has excellent mechanical property; Tensile strength can reach 800MPa, and percentage elongation reaches 28%, and-40 ℃ of low-temperature impacts reach 75J; And has good intergranular corrosion resistance characteristic, for being widely used in the welding material of anti-corrosion pressure vessel, pipeline, large-scale chemical tanker structure etc.

Claims (2)

1. a diphasic stainless steel electrode comprises core wire and coating, and coating is coated on the core wire outer wall; It is characterized in that: the weight coefficient that said coating accounts for the welding rod gross weight is 0.4～0.5; With the core wire gross weight is benchmark, percentage meter by weight, and the component of said core wire is following:

C：0.005～0.030％；

Si：0.01～0.20％；

Mn：1.50～2.50％；

P：0～0.025％；

Cr：19.0～22.0％；

Ni：9.0～11.0％；

Mo：2.5～3.5％；

Fe: surplus;

With the coating gross weight is benchmark, percentage meter by weight, and the component of said coating is following:

Calcium carbonate: 8～20%;

Brium carbonate: 2～15%;

Calcirm-fluoride: 5～15%;

Strontium fluoride: 6～17%;

Barium fluoride: 4～16%;

Ice crystal: 9～18%;

Rutile: 4～10%;

Titanium white powder: 1～5%;

Silica: 2～8%;

Chromium powder: 3～9%;

Molybdenum powder: 1～1.5%;

Magnesium powder: 0.1～4%;

Iron powder: 5～13%;

The component of said coating mixes the back and adds binding agent.

2. diphasic stainless steel electrode according to claim 1 is characterized in that: said binding agent is a potassium-sodium water glass.