CN112091475A - Preparation method of magnesium alloy welding wire - Google Patents
Preparation method of magnesium alloy welding wire Download PDFInfo
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- CN112091475A CN112091475A CN202010977511.4A CN202010977511A CN112091475A CN 112091475 A CN112091475 A CN 112091475A CN 202010977511 A CN202010977511 A CN 202010977511A CN 112091475 A CN112091475 A CN 112091475A
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- welding wire
- alloy
- magnesium alloy
- welding
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/24—Selection of soldering or welding materials proper
- B23K35/28—Selection of soldering or welding materials proper with the principal constituent melting at less than 950 degrees C
- B23K35/284—Mg as the principal constituent
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/40—Making wire or rods for soldering or welding
Abstract
A preparation method of a magnesium alloy welding wire belongs to the technical field of welding; the method comprises the following steps: heating and melting the mother alloy cast ingot under the protection of high-purity argon by an induction coil, then spraying liquid metal onto the surface of a copper roller rotating at a high speed, quickly cooling the liquid metal to obtain a welding wire, and stranding to obtain a multi-strand stranded magnesium alloy welding wire. The welding wire produced by the method has the advantages of stirring effect on molten pool metal, stable electric arc, consistent components with those of base metal, good surface quality, no surface crack and high joint strength after welding.
Description
Technical Field
The invention relates to a preparation method of a magnesium alloy welding wire.
Background
The magnesium alloy is the lightest metal structure material, and under the background of light weight of the material, the magnesium alloy is widely applied to the fields of vehicles, electronics, aerospace and the like, and the wide application of the magnesium alloy puts higher requirements on the performance of a magnesium alloy welding structural part and a welding technology. At present, the performance of welding materials is a key influence on the whole component, and the welding process and the composition and performance of welding wires determine the performance of the welded structure. Therefore, the improvement of the performance of the magnesium alloy welding material has important significance for the wide application of the magnesium alloy welding structural member.
The magnesium alloy has fast heat conduction and larger thermal expansion coefficient, and is easy to cause coarse grains, welding stress deformation and welding cracks in the welding process. Magnesium is active in chemical property, is easy to combine with oxygen at high welding temperature to generate a magnesium oxide film, has high melting point and high density, and easily forms solid slag inclusion in a molten pool, so that the welding seam performance is poor; magnesium is easy to react with nitrogen at high welding temperature to generate magnesium nitride slag, and the metal plasticity of a welding seam is also reduced. Magnesium alloys are flammable and require protection with inert gas or flux during fusion welding. The tendency of hydrogen holes generated by welding magnesium alloy is larger, and the temperature of a joint needs to be well controlled in order to prevent the base metal from generating an overheating phenomenon because a high-power heat source is usually used for welding magnesium. The commonly used welding method of magnesium alloy is argon tungsten-arc welding, under the protection of argon gas, the heat of electric arc between a tungsten electrode and a weldment is utilized to melt a base metal and a welding wire so as to complete the welding process.
At present, welding wires required in the domestic magnesium alloy welding process are mainly produced by two methods, namely casting and hot extrusion. Although the hot extrusion method can produce magnesium alloy welding wires with various diameters, when the diameter of the welding wire is less than 2.0mm, the extrusion force is multiplied, the difficulty of extrusion forming of the welding wire is increased, the straightness of the welding wire is difficult to ensure, and the drawing method has low production efficiency and high energy consumption and is not beneficial to the production of small-diameter welding wires. The welding wire is prepared by adopting an extrusion plate drawing process, the required equipment investment is large, the working procedures are large, the consumption of an extrusion die and a drawing die is large, the waste generated in each working procedure is large, and the overall finished product rate of the product is low. The magnesium alloy welding wire has the main problems of welding wire component segregation, high impurity content and hydrogen content, surface defects, and the need of controlling the chemical components of the welding wire, improving the smelting process and improving the surface quality.
The rapid solidification strip casting technology is usually used for preparing alloy thin strip materials, and the strip prepared by the rapid solidification technology has the advantages of simple process, uniform sample components and less component segregation. Compared with the block material prepared by the traditional smelting process, the method is favorable for improving the material performance, and the rapid solidification preparation technology has high controllability. A plurality of single welding wires are stranded into a plurality of strands of welding wires according to a spiral structure, the stranded welding wires are also called stranded welding wires, electric arcs rotate during welding of the stranded welding wires, a stirring effect is generated, upward floating of slag and gas is facilitated, chemical components of welding seams are uniform, and welding seam quality is improved.
Disclosure of Invention
In view of the above-mentioned deficiencies or needs for improvement in the prior art, and the practical need for welding magnesium alloy products, the present invention provides a method for preparing a magnesium alloy welding wire. The invention provides a method for preparing a magnesium alloy multi-strand stranded welding wire by using a vacuum tape-throwing machine and a stranding machine, aiming at the problems that when the diameter of the welding wire is smaller, the difficulty of extrusion forming of the welding wire is high, the production efficiency of a drawing method is lower, the energy consumption is high, and the production of the small-diameter welding wire is not facilitated. The welding wire prepared by the method has the advantages of consistent components with base metal components, pure components, low content of oxide impurities, uniform and non-segregation components, good surface quality of the welding wire, no crack and no wire breakage. The method has the advantages of small process difficulty, simple method, high efficiency, low energy consumption, more excellent welded joint quality, capability of meeting the welding use requirements of magnesium alloy products and engineering popularization value.
The purpose of the invention is realized as follows: a preparation method of a magnesium alloy welding wire comprises the following chemical components in percentage by weight: 8.5 to 9.5 percent of Al, 0.55 to 0.9 percent of Zn, 0.17 to 0.4 percent of Mn and the balance of Mg, and is characterized by comprising the following preparation steps:
preparing materials: placing pure metals of Al, Zn, Mn and Mg or alloy containing two elements in ultrasonic cleaning equipment, cleaning with an alcohol solution, drying, and weighing the dried raw materials by using an electronic balance for later use according to weight percentage;
smelting: sequentially putting all the proportioned raw materials into a graphite crucible of a vacuum induction melting furnace according to a sequence of melting points from low to high, putting the metal with the lowest melting point at the bottom of the crucible, putting the metal with the highest melting point at the top, and enabling the volume of alloy liquid to be not more than two thirds of the volume of the graphite crucible; closing the furnace cover of the vacuum furnace, and vacuumizing to 10 ℃ by using a vacuum pump-2Introducing protective gas to 20-25 MPa below Pa; starting a switch, controlling induction current to heat, keeping the molten state of the alloy and keeping the temperature 5 after the alloy is completely moltenAbout 15min, so that all alloy elements are uniformly diffused; closing the induction power supply, and quickly pouring the alloy melt into a mold to obtain a master alloy ingot;
thirdly, preparing silk: putting the obtained master alloy cast ingot into a quartz tube of a melt-spun machine, and vacuumizing a cavity to 2 multiplied by 10 by using a vacuum pump-3Introducing high-purity argon into the cavity below Pa, then melting the mother alloy ingot by high-frequency induction heating, introducing the high-purity argon into the small tank cavity when the mother alloy ingot reaches a melting state, enabling the pressure difference between the cavity and the small tank cavity to be 0.02-0.5 MPa, adjusting the wheel speed of the copper roller, directly spraying liquid metal on the copper roller rotating at a high speed through a nozzle by utilizing the pressure difference, introducing cooling water into the copper roller, and rapidly cooling the liquid metal after contacting the copper roller to form a welding wire with the length of 30-500 mm and the phi of 0.5-2 mm. Preheating the welding wire at 200-400 ℃, and then stranding the welding wire by a stranding machine to obtain a multi-strand stranded welding wire.
The invention has the advantages that:
the invention relates to a method for preparing a welding wire by using a vacuum strip throwing machine, which utilizes the consistency of the components of the welding wire and the components of a base metal under the vacuum condition, the components of the welding wire are pure, the content of oxide impurities is low, and the quality of a welded joint is excellent.
The invention relates to a method for preparing a welding wire by using a vacuum strip throwing machine, which is characterized in that molten metal is rapidly cooled on a copper rod, so that the welding wire is rapidly solidified, and the components are uniform and have no segregation.
Compared with the traditional method, the welding wire is prepared by using the vacuum tape throwing machine and the stranding machine, and the method has the advantages of small difficulty, less equipment investment, less working procedures, simple method, high efficiency, less waste generated in each working procedure, high overall product yield of products, low energy consumption and good welding wire performance.
The welding wire prepared by the invention has good surface quality, no crack, no broken wire and less surface oil stain, reduces the subsequent surface treatment links, and the production process has the characteristics of short flow processing and low cost and has engineering popularization value.
The multi-strand stranded welding wire obtained by using the components has better mechanical property after welding, and the strength of a welding joint is more than 100 MPa.
The multi-strand stranded welding wire obtained by using the components strengthens the stirring of molten pool metal, is beneficial to the stability of an electric arc process, and has unique advantages of improving the welding quality.
The welding wire with the small diameter prepared by the invention can meet the defect repair of small magnesium alloy products.
Detailed Description
TABLE 1 Properties of magnesium alloy welding wire argon tungsten-arc welding joint
A preparation method of a magnesium alloy welding wire comprises the following chemical components in percentage by weight: 8.5 to 9.5 percent of Al, 0.55 to 0.9 percent of Zn, 0.17 to 0.4 percent of Mn and the balance of Mg, and is characterized by comprising the following preparation steps:
preparing materials: placing pure metals of Al, Zn, Mn and Mg or alloy containing two elements in ultrasonic cleaning equipment, cleaning with an alcohol solution, drying, and weighing the dried raw materials by using an electronic balance for later use according to weight percentage;
smelting: sequentially putting all the proportioned raw materials into a graphite crucible of a vacuum induction melting furnace according to a sequence of melting points from low to high, putting the metal with the lowest melting point at the bottom of the crucible, putting the metal with the highest melting point at the top, and enabling the volume of alloy liquid to be not more than two thirds of the volume of the graphite crucible; closing the furnace cover of the vacuum furnace, and vacuumizing to 10 ℃ by using a vacuum pump-2Introducing protective gas to 20-25 MPa below Pa; starting a switch, controlling induction current heating, and keeping the molten state of the alloy for heat preservation for 5-15 min after the alloy is completely molten so as to uniformly diffuse all alloy elements; closing the induction power supply, and quickly pouring the alloy melt into a mold to obtain a master alloy ingot;
thirdly, preparing silk: putting the obtained master alloy cast ingot into a quartz tube of a melt-spun machine, and vacuumizing a cavity to 2 multiplied by 10 by using a vacuum pump-3Introducing high-purity argon into the cavity below Pa, then melting the mother alloy ingot by high-frequency induction heating, introducing the high-purity argon into the small tank cavity when the mother alloy ingot reaches a melting state, enabling the pressure difference between the cavity and the small tank cavity to be 0.02-0.5 MPa, adjusting the wheel speed of the copper roller, and directly spraying liquid metal on the high-speed rotating copper roller through a nozzle by utilizing the pressure differenceAnd cooling water is introduced into the copper roller, and the liquid metal is rapidly cooled after contacting the copper roller to form a welding wire with the length of 30-500 mm and the phi of 0.5-2 mm. Preheating the welding wire at 200-400 ℃, and then stranding the welding wire by a stranding machine to obtain a multi-strand stranded welding wire.
And fourthly, performing a welding test on the AZ91 magnesium alloy multi-strand stranded welding wire prepared by the method, wherein the diameter of the welding wire is 1.6-4 mm, the base material is AZ91D, and the welding method is argon tungsten-arc welding. The size of a base metal is 100 multiplied by 200 multiplied by 100mm, the bottom of the base metal is an arc V-shaped groove, the width of the groove is 20mm, the depth of the groove is 15mm, the welding current is 300-450A, the arc voltage is 25-30V, the diameter of a tungsten electrode is 3mm, the argon flow is 18-25L/min, the base metal and a welding wire are mechanically cleaned before welding, a high-frequency alternating current power supply is adopted for welding, and the welding speed is about 200-280 mm/min. And overlaying layer by layer until the whole groove is filled.
TABLE 1 Properties of magnesium alloy welding wire argon tungsten-arc welding joint
| Examples of the invention | Tensile strength (MPa) | Hardness (HV) |
| Examples of the invention | 115MPa | 195 |
Claims (8)
1. A preparation method of a magnesium alloy welding wire comprises the following chemical components in percentage by weight: 8.5 to 9.5 percent of Al, 0.55 to 0.9 percent of Zn, 0.17 to 0.4 percent of Mn and the balance of Mg, and is characterized by comprising the following preparation steps:
preparing materials: placing pure metals of Al, Zn, Mn and Mg or alloy containing two elements in ultrasonic cleaning equipment, cleaning with an alcohol solution, drying, and weighing the dried raw materials by using an electronic balance for later use according to weight percentage;
smelting: sequentially putting all the proportioned raw materials into a graphite crucible of a vacuum induction melting furnace according to a sequence of melting points from low to high, putting the metal with the lowest melting point at the bottom of the crucible, putting the metal with the highest melting point at the top, and enabling the volume of alloy liquid to be not more than two thirds of the volume of the graphite crucible; closing the furnace cover of the vacuum furnace, and vacuumizing to 10 ℃ by using a vacuum pump-2Introducing protective gas to 20-25 MPa below Pa; starting a switch, controlling induction current heating, and keeping the molten state of the alloy for heat preservation for 5-15 min after the alloy is completely molten so as to uniformly diffuse all alloy elements; closing the induction power supply, and quickly pouring the alloy melt into a mold to obtain a master alloy ingot;
thirdly, preparing silk: putting the obtained master alloy cast ingot into a quartz tube of a melt-spun machine, and vacuumizing a cavity to 2 multiplied by 10 by using a vacuum pump-3Introducing high-purity argon into the cavity below Pa, then melting the mother alloy ingot by high-frequency induction heating, introducing the high-purity argon into the small tank cavity when the mother alloy ingot reaches a melting state, enabling the pressure difference between the cavity and the small tank cavity to be 0.02-0.5 MPa, adjusting the wheel speed of the copper roller, directly spraying liquid metal on the copper roller rotating at a high speed through a nozzle by utilizing the pressure difference, introducing cooling water into the copper roller, and rapidly cooling the liquid metal after contacting the copper roller to form a welding wire with the length of 30-500 mm and the phi of 0.5-2 mm. Preheating the prepared welding wire at 200-400 ℃, and stranding the welding wire by a stranding machine to obtain a multi-strand stranded welding wire.
2. The preparation method of the magnesium alloy welding wire according to claim 1, wherein the mother alloy ingot has a diameter of 10-15 mm and a length of 70-120 mm.
3. The preparation method of the magnesium alloy welding wire according to claim 1, wherein the size of the copper roller is phi 220 x 40mm, and the surface linear velocity of the copper roller is 0-49 m/s.
4. The preparation method of the magnesium alloy welding wire according to claim 1, wherein the quartz tube is 150mm long, 18mm in outer diameter, 16mm in inner diameter and 0-2 mm in nozzle diameter.
5. The method for preparing the magnesium alloy welding wire according to claim 1, wherein the distance between the nozzle and the copper rod is 1-3 mm.
6. The preparation method of the magnesium alloy welding wire according to claim 1, wherein the high-frequency induction heating power is 5-20 kw, the melting current is controlled to be 20-50A, and the heating temperature is 600-700 ℃.
7. The method for preparing the magnesium alloy welding wire according to claim 1, wherein the diameter of the stranded welding wire is 1-4 mm, the stranded welding wire is of a 1 x 3 structure, and 3 welding wires are twisted with each other in a spiral shape.
8. The method for preparing the magnesium alloy welding wire according to claim 1, wherein the lay length of the stranding machine is 4-20 times of the equivalent diameter of the stranded welding wire, the rotation speed is 200-500 r/min, and the tension is 10-15% of the rated value of the tension of the device.
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| CN202010977511.4A CN112091475A (en) | 2020-09-16 | 2020-09-16 | Preparation method of magnesium alloy welding wire |
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| CN202010977511.4A CN112091475A (en) | 2020-09-16 | 2020-09-16 | Preparation method of magnesium alloy welding wire |
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|---|---|---|---|---|
| AU2005293816A1 (en) * | 2004-10-15 | 2006-04-20 | Aleris Aluminum Koblenz Gmbh | Al-Mg-Mn weld filler alloy |
| CN106001984A (en) * | 2016-06-14 | 2016-10-12 | 江苏阳明船舶装备制造技术有限公司 | Magnesium alloy brazing filler metal based on rare earth magnesium alloy braze as well as preparation method and brazing technology of magnesium alloy brazing filler metal |
| CN106002001A (en) * | 2016-06-26 | 2016-10-12 | 周荣 | Method for preparing magnesium alloy thin strip brazing filler metal from waste powder coal dust through modification |
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| CN108555477A (en) * | 2018-07-11 | 2018-09-21 | 河南维可托镁合金科技有限公司 | A kind of magnesium alloy solder wire and preparation method thereof |
| CN109623200A (en) * | 2019-01-18 | 2019-04-16 | 江苏联捷焊业科技有限公司 | A kind of strand type submerged arc flux-cored wire and preparation method thereof having both high efficiency and crack resistance |
| CN110014246A (en) * | 2019-05-09 | 2019-07-16 | 宁夏中太镁业科技有限公司 | A kind of welding wire and preparation method thereof for welding magnesium alloy materials |
| CN110614458A (en) * | 2019-09-19 | 2019-12-27 | 河北联之捷焊业科技有限公司 | High-strength steel submerged arc stranded welding wire and welding method thereof |
| CN110936050A (en) * | 2019-11-21 | 2020-03-31 | 河北联之捷焊业科技有限公司 | Stranded welding wire for high-strength steel and preparation process thereof |
-
2020
- 2020-09-16 CN CN202010977511.4A patent/CN112091475A/en active Pending
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|---|---|---|---|---|
| AU2005293816A1 (en) * | 2004-10-15 | 2006-04-20 | Aleris Aluminum Koblenz Gmbh | Al-Mg-Mn weld filler alloy |
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| CN110614458A (en) * | 2019-09-19 | 2019-12-27 | 河北联之捷焊业科技有限公司 | High-strength steel submerged arc stranded welding wire and welding method thereof |
| CN110936050A (en) * | 2019-11-21 | 2020-03-31 | 河北联之捷焊业科技有限公司 | Stranded welding wire for high-strength steel and preparation process thereof |
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Application publication date: 20201218 |