阅读说明：本技术 连铸机弯曲段连铸辊堆焊用明弧自保护药芯焊丝及其制法 (Open arc self-protection flux-cored wire for surfacing of continuous casting roller at bending section of continuous casting machine and manufacturing method thereof ) 是由 张建 李彬周 徐晓东 王期文 高品 孙沛沛 王军生 于 2019-09-29 设计创作，主要内容包括：一种连铸机弯曲段连铸辊堆焊用明弧自保护药芯焊丝,由药粉和低碳钢钢带组成。药粉占焊丝总重量为36～40％,药粉各组分占药粉的质量百分比为：4.2～6.5％金属镍粉,1～2.6％钼铁,1～1.4％铌铁,18～23％微碳铬铁,1.5～2.8％氮化铬,0.8～1.7％45#硅铁,1.5～2.8％电解锰,0.15～0.32％氟铝酸钠,1.1～2.5％白云石,4.2～8.5％金红石,1.5～2.9％萤石,0.3～0.5％铝粉,0.2～0.4％镁粉,其余为铁粉。基本材料为冷轧低碳钢带,含碳量为0.05～0.08％。焊接工艺性能优良,成型美观,飞溅较小,堆焊层金属为铬、镍、钼低碳合金,抗氧化,耐腐蚀,耐磨损和耐冷热疲劳性能优良。(An open arc self-protection flux-cored wire for surfacing of a continuous casting roller at a bending section of a continuous casting machine comprises powder and a low-carbon steel strip. The powder accounts for 36-40% of the total weight of the welding wire, and the powder comprises the following components in percentage by mass: 4.2-6.5% of metallic nickel powder, 1-2.6% of ferromolybdenum, 1-1.4% of ferroniobium, 18-23% of micro-carbon ferrochromium, 1.5-2.8% of chromium nitride, 0.8-1.7% of 45# ferrosilicon, 1.5-2.8% of electrolytic manganese, 0.15-0.32% of sodium fluoroaluminate, 1.1-2.5% of dolomite, 4.2-8.5% of rutile, 1.5-2.9% of fluorite, 0.3-0.5% of aluminum powder, 0.2-0.4% of magnesium powder and the balance of iron powder. The basic material is a cold-rolled low-carbon steel strip, and the carbon content is 0.05-0.08%. The welding process has excellent performance, attractive appearance and less splashing, and the metal of the overlaying layer is chromium, nickel and molybdenum low-carbon alloy, so that the overlaying layer has excellent oxidation resistance, corrosion resistance, wear resistance and cold and hot fatigue resistance.)

1. The open arc self-protection flux-cored wire for surfacing of the continuous casting roller at the bending section of the continuous casting machine is composed of powder and a low-carbon steel strip, and is characterized in that the powder accounts for 36-40% of the total weight of the wire, and the powder comprises the following components in percentage by mass: 4.2-6.5% of metallic nickel powder, 1-2.6% of ferromolybdenum, 1-1.4% of ferroniobium, 18-23% of micro-carbon ferrochromium, 1.5-2.8% of chromium nitride, 0.8-1.7% of 45# ferrosilicon, 1.5-2.8% of electrolytic manganese, 0.15-0.32% of sodium fluoroaluminate, 1.1-2.5% of dolomite, 4.2-8.5% of rutile, 1.5-2.9% of fluorite, 0.3-0.5% of aluminum powder, 0.2-0.4% of magnesium powder and the balance of iron powder.

2. The open arc self-protection flux-cored wire for overlaying welding of the continuous casting roller at the bending section of the continuous casting machine according to claim 1, wherein the carbon content of the low-carbon steel strip is in a range of 0.05-0.08%.

Technical Field

The invention belongs to the technical field of surfacing welding, and particularly relates to an open arc self-protection flux-cored wire for surfacing welding of a bending section continuous casting roller and a preparation method thereof.

Background

The continuous casting roll is a main consumable part in continuous casting equipment, and the service life of the continuous casting roll directly determines the cost and the production continuity of a continuous casting process, so that the research on advanced surfacing materials to prolong the service life of the continuous casting roll is of great significance. The continuous casting roll comprises a foot roll, a supporting guide roll, a bending section continuous casting roll, an arc section continuous casting roll, a straightening section continuous casting roll and a horizontal section continuous casting roll. The roll surface temperature of the bending section continuous casting roll is high, and the bending section continuous casting roll bears serious mechanical force and bulging force of steel billets. Meanwhile, the acidic water-absorbing ferric chloride salt reacts with water to generate acid, which easily causes the erosion of the overlaying layer. The failure mechanisms of the curved segment continuous casting rolls are therefore fatigue cracking and stress corrosion.

The traditional manufacturing method of the bending section continuous casting roller is to weld the Cr13 series martensitic stainless steel on the surface of the roller blank by submerged arc surfacing, but because of the insufficient cold and hot fatigue resistance and corrosion resistance and the limitation of the submerged arc surfacing process, the roller surface is easy to generate stress corrosion and fatigue cracks in the using process, and the service life is seriously reduced.

Compared with submerged arc welding, open arc surfacing has the main characteristics of less heat input quantity to a workpiece, small workpiece deformation degree, simple welding process, no need of heat treatment before and after welding, energy conservation, high deposition efficiency, strong stability and uniform hardness of a deposition layer, and is particularly suitable for surfacing of small-roller-diameter and hollow roller ways.

Disclosure of Invention

In view of the problems of the prior art, the surfacing material for the continuous casting roller of the bending section should be resistant to stress corrosion, high-temperature oxidation and high-temperature deformation. The invention aims to provide an open arc self-protection flux-cored wire for overlaying a bending section continuous casting roller and a preparation method thereof, so as to prolong the service life of the bending section continuous casting roller.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

An open arc self-protection flux-cored wire for surfacing of a continuous casting roller at a bending section of a continuous casting machine comprises powder and a low-carbon steel strip. The powder accounts for 36-40% of the total weight of the welding wire, and the powder comprises the following components in percentage by mass: 4.2-6.5% of metallic nickel powder, 1-2.6% of ferromolybdenum, 1-1.4% of ferroniobium, 18-23% of micro-carbon ferrochromium, 1.5-2.8% of chromium nitride, 0.8-1.7% of 45# ferrosilicon, 1.5-2.8% of electrolytic manganese, 0.15-0.32% of sodium fluoroaluminate, 1.1-2.5% of dolomite, 4.2-8.5% of rutile, 1.5-2.9% of fluorite, 0.3-0.5% of aluminum powder, 0.2-0.4% of magnesium powder and the balance of iron powder. The basic material is a cold-rolled low-carbon steel strip, and the carbon content is 0.05-0.08%.

The nickel powder provides Ni element for the surfacing welding cladding layer, Ni can expand a gamma region, a stable martensite structure of the cladding layer can be ensured even if the content of C is very low, and meanwhile, Ni can improve the tempering resistance of martensite and increase the high-temperature toughness of the martensite. The molybdenum iron contains 55-60% of Mo, and provides Mo element for the surfacing welding cladding layer, and mainly improves the tempering stability and the high-temperature strength. The Nb content of the ferrocolumbium is 62-66%, Nb elements are provided for the surfacing welding cladding layer, the precipitation of niobium carbide is mainly increased, and the high-temperature strength and the wear resistance are improved. The micro-carbon ferrochrome is used for transferring Cr and C to a surfacing welding cladding layer, the carbon content is 0.06-0.08%, the chromium content is 65-68%, and Cr has the function of forming Cr nitride on the surface at high temperature so as to improve the oxidation resistance and improve the strength and hardness of a cladding layer metal. Chromium nitride containing 60% Cr and 5.2% N, which mainly provides Cr and N to the cladding layer metal. The Si and Mn elements in the Si-Fe and electrolytic manganese contribute to deoxidation and an excessive amount of Si and Mn is added to the cladding layer. The rest ore powder materials such as sodium fluoroaluminate, dolomite, rutile, fluorite, aluminum powder, magnesium powder and the like mainly play roles in arc stabilization, slagging and gas making.

The diameter of the flux-cored wire is 2.4 mm.

The preparation method of the flux-cored wire comprises the following steps:

1. Mixing the medicinal powders according to the mass percentage to obtain mixed medicinal powders, mixing and stirring for 30-50 minutes, and then putting into a furnace for drying, wherein the drying temperature is 300-350 ℃, and the drying time is 3-5 hours.

2.0.3 mm 16mm low carbon stainless steel band is washed, dried and rolled into U shape.

3. And filling powder into the U-shaped groove, wherein the powder accounts for 36-40% of the total weight of the welding wire.

And 4, rolling the U-shaped groove into a circular shape, and continuously rolling and drawing to reduce the diameter to finally obtain the welding wire with the diameter of 2.4, namely the open arc self-protection flux-cored wire for the foot roll surfacing of the continuous casting crystallizer.

Compared with the prior art, the invention has the beneficial effects that:

The open arc self-protection flux-cored wire for surfacing of the continuous casting roller at the bending section of the continuous casting machine has the advantages of excellent welding process performance, attractive forming and less splashing, and the surfacing layer is made of chromium, nickel and molybdenum low-carbon alloy, and has excellent oxidation resistance, corrosion resistance, wear resistance and cold and thermal fatigue resistance.

Detailed Description

the present invention will be further described with reference to the following examples.