Machining method for preparing titanium welding wire through multi-roller die combined drawing

Abstract

The invention discloses a processing method for preparing a titanium welding wire through multi-roller die combined drawing, which comprises the following steps of: 1, rounding a titanium bar, and peeling to obtain a bar to be subjected to roller die drawing; secondly, first-time roller die drawing is carried out, and a first-time roller die bar is obtained; thirdly, primary vacuum annealing is carried out, and a primary roller die bar after vacuum annealing is obtained; fourthly, secondary roller die drawing is conducted, and a secondary roller die bar is obtained; fifthly, third-time roller die drawing is conducted, and a third-time roller die bar is obtained; and sixthly, finished product vacuum annealing and polishing are conducted, and the titanium welding wire is obtained. Initial primary large deformation of the titanium bar is achieved through primary roller die drawing, the stress of the initial primary large deformation of the titanium bar is eliminated through primary vacuum annealing, primary moderate deformation of the titanium bar in the middle process is achieved through secondary roller die drawing, primary small deformation of the titanium bar is achieved through tertiary roller die drawing, and the titanium bar is subjected to secondary vacuum annealing. And the stress is eliminated and the surface smoothness is guaranteed through vacuum annealing of a finished product, so that the titanium welding wire with excellent performance is obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium wire preparation, and in particular relates to a processing method for preparing titanium welding wire by multi-roller die combined drawing. Background Art

[0002] Titanium and titanium alloys are increasingly used in aviation, aerospace, shipbuilding, chemical industry, petroleum, biomedicine and other fields due to their high specific strength, excellent comprehensive mechanical properties, good corrosion resistance, excellent biocompatibility and other characteristics. Titanium products account for about 60% of all titanium alloy products, among which titanium wire occupies an important market position due to welding demand.

[0003] The specifications of titanium welding wires commonly used in industry are between Φ2.0mm and Φ3.0mm. The traditional preparation process is mainly based on repeated hot drawing of fixed molds. In addition, preheating treatment is required before hot drawing and annealing treatment is interspersed during the drawing process. Since the deformation amount of a single fixed drawing is limited and only one mold can be passed each time, multiple drawing is required to achieve the final specifications. At the same time, each hot drawing requires preheating treatment, which increases the production cycle. In addition, due to the accumulation of deformation, the processing stress increases and it is difficult to continue to deform. At the same time, during the hot deformation process, titanium contacts with harmful elements such as hydrogen, oxygen and nitrogen in the atmosphere, causing the gas elements to exceed the standard. Vacuum annealing is required in the middle of the drawing to eliminate the processing stress and reduce the gas element content. The whole process is complicated, inefficient, wastes a lot of materials, and the quality of the final product is not high.

[0004] Therefore, there is an urgent need for an improved method for preparing titanium welding wire. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a processing method for preparing titanium welding wire by multi-roller die combined drawing in view of the deficiencies of the above-mentioned prior art. The method mainly realizes the initial large deformation of the titanium bar through the first roller die drawing, mainly eliminates the stress of the initial large deformation of the titanium bar through a vacuum annealing, mainly realizes a moderate deformation of the titanium bar in the middle process through the second roller die drawing, mainly realizes a small deformation of the titanium bar through the third roller die drawing, eliminates the stress of the titanium welding wire and ensures the surface finish through the finished product vacuum annealing, and obtains the titanium welding wire.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a processing method for preparing titanium welding wire by multi-roller die combined drawing, characterized in that the method comprises the following steps:

[0007] Step 1: Round the titanium rod to obtain a round rod, and then peel the round rod to obtain a rod to be drawn by a roller die.

[0008] Step 2: subjecting the rod to be roller-die-drawn obtained in step 1 to a first roller-die-drawn rod.

[0009] Step 3, performing a vacuum annealing on the primary roller die bar obtained in step 2 to obtain a primary roller die bar after vacuum annealing, mainly eliminating the stress of the initial large deformation of the titanium bar;

[0010] Step 4: subjecting the vacuum annealed primary roller die bar obtained in step 3 to a second roller die drawing to obtain a secondary roller die bar.

[0011] Step 5: subject the secondary roller die rod obtained in step 4 to a third roller die drawing to obtain a tertiary roller die rod.

[0012] Step 6: The three-roller die bar obtained in step 5 is subjected to vacuum annealing and then surface polishing to obtain titanium welding wire.

[0013] The present invention adopts the titanium rod obtained by hot rolling, which is convenient for quickly processing the titanium raw material into the titanium rod, and the roundness and surface finish are guaranteed by rounding and peeling, which is convenient for subsequent multi-roller die drawing. The first roller die drawing mainly realizes the initial large deformation of the titanium rod, and the stress of the initial large deformation of the titanium rod is mainly eliminated by a vacuum annealing. The second roller die drawing mainly realizes a moderate deformation of the titanium rod in the middle process, and the third roller die drawing mainly realizes a small deformation of the titanium rod. The stress of the titanium welding wire is eliminated and the surface finish is guaranteed by the vacuum annealing of the finished product, so as to obtain the titanium welding wire.

[0014] The above-mentioned processing method for preparing titanium welding wire by multi-roller die combined drawing is characterized in that the diameter of the titanium rod in step one is 8mm-9mm, the rounding deformation in the rounding is 8.7%-9.8%, and the diameter of the rounding rod is 7.6mm-8.6mm; the peeling is performed using a centerless lathe, the peeling amount is 0.3mm-0.4mm, the diameter of the rod to be drawn by the roller die is 7.2mm-8.2mm, and the surface is bright. The present invention facilitates processing by controlling the size of the titanium rod to obtain a titanium welding wire of a suitable size, and controls the roundness and surface finish of the rod to be drawn by the roller die by controlling the parameters of the rounding and peeling, thereby laying a good foundation for the first roller die drawing.

[0015] The above-mentioned method for preparing titanium welding wire by drawing with a combination of multiple roller dies is characterized in that the first roller die drawing in step 2 is a continuous drawing of a combination of four roller dies, a single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies, the deformation of the roller dies is 11.8% to 18.7%, the total deformation is 46.5% to 51.8%, the drawing speed is 80m / min to 100m / min, and the diameter of the first roller die bar is 5.0mm to 6.0mm. The present invention ensures the effect of roller die drawing by using a combination of four roller dies for continuous drawing, and by controlling the parameters of the first roller die drawing, the bar to be drawn by the roller die is subjected to a large deformation, which is convenient for subsequent processing and provides a basis for the preparation of titanium welding wire.

[0016] The above-mentioned method for preparing titanium welding wire by multi-roller die combined drawing is characterized in that the temperature of vacuum annealing in step 3 is 600°C to 650°C and the time is 120min to 180min. The present invention fully eliminates the stress of the first roller die drawing, i.e., the first large deformation, and ensures the smoothness by controlling the parameters of vacuum annealing.

[0017] The above-mentioned processing method for preparing titanium welding wire by multi-roller die combined drawing is characterized in that the second roller die drawing in step 4 is a continuous drawing of four groups of roller dies, a single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies, the deformation of each roller die is 9.7% to 19.5%, the total deformation is 38.9% to 51.0%, the drawing speed is 100m / min to 120m / min, and the diameter of the secondary roller die bar is 3.5mm to 4.5mm. The present invention ensures the effect of roller die drawing by using four groups of roller die combined continuous drawing, and by controlling the parameters of the second roller die drawing, the primary roller die bar is subjected to a moderate amount of deformation in the intermediate process, which is convenient for subsequent processing and provides a basis for the preparation of titanium welding wire.

[0018] The above-mentioned method for preparing titanium welding wire by drawing with a combination of multiple roller dies is characterized in that the third roller die drawing in step five is a continuous drawing of a combination of four roller dies, a single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies, the deformation of each roller die is 12.9% to 27.0%, the total deformation is 54.7% to 65.7%, the drawing speed is 100m / min to 120m / min, and the diameter of the three roller die bars is 2.05mm to 3.05mm. The present invention ensures the effect of roller die drawing by using a combination of four roller dies for continuous drawing, and by controlling the third roller die drawing parameters, the secondary roller die bar is deformed with a smaller deformation amount, which is convenient for the precise control of the size of the titanium welding wire and the preparation of titanium welding wire of suitable size.

[0019] The above-mentioned method for preparing titanium welding wire by multi-roller die combined drawing is characterized in that the temperature of the finished product vacuum annealing in step six is ​​600℃~650℃, the time is 120min~180min, the grinding thickness in the surface polishing is 0.03mm~0.05mm, and the diameter of the titanium welding wire is 2.0mm~3.0mm. The present invention fully eliminates deformation stress by controlling the parameters of vacuum annealing, ensures the accuracy of the titanium welding wire size and surface finish by controlling the grinding thickness, and realizes the preparation of high-quality titanium welding wire.

[0020] The above-mentioned method for preparing titanium welding wire by multi-roller die combined drawing is characterized in that heating oxidation and surface coating are not required before the first roller die drawing in step 2, the second roller die drawing in step 4, and the third roller die drawing in step 5. In the present invention, due to the bite advantage of roller die drawing, heating oxidation and surface coating are not required before roller die drawing, which improves the working environment of the drawing process and makes the production process more environmentally friendly.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] 1. The present invention adopts the titanium rod obtained by hot rolling, which is convenient for quickly processing the titanium raw material into the titanium rod. The roundness and surface finish are guaranteed by rounding and peeling, which is convenient for subsequent multi-roller die drawing. The first roller die drawing mainly realizes the initial large deformation of the titanium rod. The primary vacuum annealing mainly eliminates the stress of the initial large deformation of the titanium rod. The second roller die drawing mainly realizes a moderate deformation of the titanium rod in the middle process. The third roller die drawing mainly realizes a small deformation of the titanium rod. The finished product vacuum annealing eliminates the stress of the titanium welding wire and ensures the surface finish, thereby obtaining the titanium welding wire.

[0023] 2. The present invention combines multiple groups of roller dies to facilitate large deformation processing of titanium welding wire. In addition, it has the advantages of extremely high drawing speed, less intermediate heat treatment times, less product pollution during the production process, uniform product size and high quality.

[0024] 3. In the present invention, the titanium rod does not need to be preheated, and can be directly subjected to continuous drawing by multiple sets of roller dies. Compared with the solid die drawing hot drawing speed of 1m / min to 4m / min, the continuous drawing speed of multiple combination roller dies is 80m / min to 120m / min, and the deformation of each roller die is 8% to 20% higher than that of the solid die, which greatly improves the production efficiency. It only needs to undergo two vacuum heat treatments, which is 2 to 3 times less than the conventional method, thereby reducing the pollution of the wire during the operation process, improving the production efficiency, reducing the production cost, and improving the quality of the titanium welding wire.

[0025] 4. In the process of pretreatment of the rod blank before drawing, the present invention does not need to heat and oxidize the surface, nor use lubricant coating. The production process is more environmentally friendly than the traditional one. In addition, the pretreatment process does not require heating, which reduces production costs and improves efficiency.

[0026] 5. The drawing speed of the multi-roller die combination drawing of the present invention is one to two orders of magnitude faster than that of the traditional fixed die, and the deformation amount is large, and the production efficiency is greatly improved. Compared with the traditional fixed die hot drawing, the processing method of preparing titanium welding wire by multi-roller die combination drawing of the present invention is in the process of cold deformation of the wire material during the processing, and there is no contact with harmful elements such as oxygen, nitrogen and hydrogen during the heating process, which reduces the pollution of harmful elements. In addition, the material structure is more uniform.

[0027] 6. The present invention continuously draws titanium welding wire through a roller die combination. Each drawing process is continuously drawn through four dies. The total deformation is about 38.5% to 65.7%, and the drawing speed is 80m / min to 120m / min. The deformation is large, the drawing speed is high, and the process is simple.

[0028] The technical solution of the present invention is further described in detail below through embodiments. DETAILED DESCRIPTION

[0029] Example 1

[0030] This embodiment includes the following steps:

[0031] Step 1: The titanium rod with a diameter of 8 mm obtained by hot rolling is rounded using a wire drawing machine, and the rounding deformation is 9.8%, so as to obtain a round rod with a diameter of 7.6 mm. Then, the round rod is stripped using a centerless lathe, and the stripping amount is 0.4 mm, so as to obtain a bright roller die drawing rod with a diameter of 7.2 mm;

[0032] Step 2: The shiny rod to be drawn by roller die with a diameter of 7.2 mm obtained in step 1 is subjected to the first roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 13.4%, 17.1%, 18.7% and 17.4% respectively, and the total deformation is 51.8%. The drawing speed is 80 m / min, and a primary roller die rod with a diameter of 5.0 mm is obtained; heating oxidation and surface coating are not required before the first roller die drawing;

[0033] Step 3: Perform vacuum annealing on the primary roller die bar with a diameter of 5.0 mm obtained in step 2, with the annealing temperature being 600° C. and the time being 120 min, to obtain a primary roller die bar with a diameter of 5.0 mm after vacuum annealing;

[0034] Step 4: The vacuum annealed primary roller die bar with a diameter of 5.0 mm obtained in step 3 is subjected to a second roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 11.6%, 16.3%, 17.7% and 19.5% respectively, and the total deformation is 51%. The drawing speed is 100 m / min, and a secondary roller die bar with a diameter of 3.5 mm is obtained; heating oxidation and surface coating are not required before the second roller die drawing;

[0035] Step 5: The secondary roller die bar with a diameter of 3.5 mm obtained in step 4 is subjected to a third roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 16.4%, 23.4%, 26.5% and 27% respectively, and the total deformation is 65.7%. The drawing speed is 100 m / min, and a tertiary roller die bar with a diameter of 2.05 mm is obtained; heating oxidation and surface coating are not required before the third roller die drawing;

[0036] Step 6: The three-roller die bar with a diameter of 2.05 mm obtained in step 5 is subjected to finished vacuum annealing at a temperature of 600° C. for 120 min, followed by surface polishing with a grinding thickness of 0.05 mm to obtain a titanium welding wire with a diameter of 2.00 mm.

[0037] After testing, the hydrogen content of the titanium welding wire prepared in this embodiment is 0.003%, which meets the requirements (the standard requires the hydrogen content to be less than 0.008%), and the diameters of multiple parts of the titanium welding wire are measured, which are 2.003mm, 2.005mm, and 2.004mm respectively, which meet the national standard requirements.

[0038] Example 2

[0039] This embodiment includes the following steps:

[0040] Step 1: The titanium bar with a diameter of 9 mm obtained by hot rolling is rounded using a wire drawing machine, and the rounding deformation is 8.7%, so as to obtain a rounded bar with a diameter of 8.6 mm. Then, the rounded bar is stripped using a centerless lathe, and the stripping amount is 0.4 mm, so as to obtain a bright roller die drawing bar with a diameter of 8.2 mm;

[0041] Step 2: The shiny rod to be drawn by roller die with a diameter of 8.2 mm obtained in step 1 is subjected to the first roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 11.8%, 15.0%, 16.2% and 14.8% respectively, and the total deformation is 46.5%. The drawing speed is 100 m / min, and a primary roller die rod with a diameter of 6.0 mm is obtained; heating oxidation and surface coating are not required before the first roller die drawing;

[0042] Step 3: Perform vacuum annealing on the primary roller die bar with a diameter of 6.0 mm obtained in step 2, with the annealing temperature being 650° C. and the time being 180 min, to obtain a primary roller die bar with a diameter of 6.0 mm after vacuum annealing;

[0043] Step 4: The primary roller die bar with a diameter of 6.0 mm obtained after vacuum annealing in step 3 is subjected to a second roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 9.3%, 13.5%, 14.5% and 15.7% respectively, and the total deformation is 43.8%. The drawing speed is 120 m / min, and a secondary roller die bar with a diameter of 4.5 mm is obtained; heating oxidation and surface coating are not required before the second roller die drawing;

[0044] Step 5: The secondary roller die bar with a diameter of 4.5 mm obtained in step 4 is subjected to a third roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 12.9%, 18.1%, 19.9% ​​and 20.6% respectively, and the total deformation is 54.7%. The drawing speed is 110 m / min, and a tertiary roller die bar with a diameter of 3.03 mm is obtained; heating oxidation and surface coating are not required before the third roller die drawing;

[0045] Step 6: The three-roller die bar with a diameter of 3.03 mm obtained in step 5 is subjected to finished product vacuum annealing at a temperature of 650°C for 180 min, followed by surface polishing with a grinding thickness of 0.03 mm to obtain a titanium welding wire with a diameter of 3.00 mm.

[0046] After testing, the hydrogen content of the titanium welding wire prepared in this embodiment is 0.003%, which meets the requirements (the standard requires the hydrogen content to be less than 0.008%), and the diameters of multiple parts of the titanium welding wire are measured, which are 3.003mm, 3.005mm, and 3.004mm respectively, which meet the national standard requirements.

[0047] Example 3

[0048] This embodiment includes the following steps:

[0049] Step 1: The titanium rod with a diameter of 8 mm obtained by hot rolling is rounded using a wire drawing machine, and the rounding deformation is 9.8%, so as to obtain a round rod with a diameter of 7.6 mm. Then, the round rod is stripped using a centerless lathe, and the stripping amount is 0.3 mm, so as to obtain a bright roller die drawing rod with a diameter of 7.3 mm;

[0050] Step 2: The shiny rod to be drawn by roller die with a diameter of 7.3 mm obtained in step 1 is subjected to the first roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 13.2%, 14.2%, 15.2% and 16.5% respectively, and the total deformation is 47.3%. The drawing speed is 80 m / min, and a primary roller die rod with a diameter of 5.3 mm is obtained; heating oxidation and surface coating are not required before the first roller die drawing;

[0051] Step 3: Perform vacuum annealing on the primary roller die bar with a diameter of 5.3 mm obtained in step 2, with the annealing temperature being 630° C. and the time being 150 min, to obtain a primary roller die bar with a diameter of 5.3 mm after vacuum annealing;

[0052] Step 4: The vacuum annealed primary roller die bar with a diameter of 5.3 mm obtained in step 3 is subjected to a second roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 11.0%, 11.6%, 12.4% and 13.2% respectively, and the total deformation is 40.2%. The drawing speed is 100 m / min, and a secondary roller die bar with a diameter of 4.1 mm is obtained; heating oxidation and surface coating are not required before the second roller die drawing;

[0053] Step 5: The secondary roller die bar with a diameter of 4.1 mm obtained in step 4 is subjected to a third roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 18.6%, 20.5%, 22.8% and 23.3% respectively, and the total deformation is 61.6%. The drawing speed is 100 m / min, and a tertiary roller die bar with a diameter of 2.54 mm is obtained; heating oxidation and surface coating are not required before the third roller die drawing;

[0054] Step 6: The three-roller die bar with a diameter of 2.54 mm obtained in step 5 is subjected to vacuum annealing at a temperature of 630°C for 150 min, followed by surface polishing with a grinding thickness of 0.04 mm to obtain a titanium welding wire with a diameter of 2.5 mm.

[0055] After testing, the hydrogen content of the titanium welding wire prepared in this embodiment is 0.002%, which meets the requirements (the standard requires the hydrogen content to be less than 0.008%), and the diameters of multiple parts of the titanium welding wire are measured, which are 2.503mm, 2.502mm, and 2.503mm respectively, which meet the national standard requirements.

[0056] Example 4

[0057] This embodiment includes the following steps:

[0058] Step 1: The titanium rod with a diameter of 8.5 mm obtained by hot rolling is rounded using a wire drawing machine, and the rounding deformation is 9.2%, so as to obtain a round rod with a diameter of 8.1 mm. Then, the round rod is stripped using a centerless lathe, and the stripping amount is 0.4 mm, so as to obtain a bright roller die drawing rod with a diameter of 7.7 mm;

[0059] Step 2: The shiny rod to be drawn by roller die with a diameter of 7.7 mm obtained in step 1 is subjected to the first roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 12.6%, 16.0%, 17.4% and 16.0% respectively, and the total deformation is 49.0%. The drawing speed is 90 m / min, and a primary roller die rod with a diameter of 5.5 mm is obtained; heating oxidation and surface coating are not required before the first roller die drawing;

[0060] Step 3: Perform vacuum annealing on the primary roller die bar with a diameter of 5.5 mm obtained in step 2, with the annealing temperature being 650° C. and the time being 150 min, to obtain a primary roller die bar with a diameter of 5.5 mm after vacuum annealing;

[0061] Step 4: The primary roller die bar with a diameter of 5.5 mm obtained after vacuum annealing in step 3 is subjected to a second roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 10.6%, 11.2%, 11.9% and 12.6% respectively, and the total deformation is 38.9%. The drawing speed is 110 m / min, and a secondary roller die bar with a diameter of 4.3 mm is obtained; heating oxidation and surface coating are not required before the second roller die drawing;

[0062] Step 5: The secondary roller die bar with a diameter of 4.3 mm obtained in step 4 is subjected to a third roller die drawing, and four groups of roller dies are used for continuous drawing. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 13.5%, 19.0%, 21.0% and 20.7% respectively, and the total deformation is 56.1%. The drawing speed is 120 m / min, and a tertiary roller die bar with a diameter of 2.85 mm is obtained; heating oxidation and surface coating are not required before the third roller die drawing;

[0063] Step 6: The three-roller die bar with a diameter of 2.85 mm obtained in step 5 is subjected to finished product vacuum annealing at a temperature of 650°C for 180 min, followed by surface polishing with a grinding thickness of 0.05 mm to obtain a titanium welding wire with a diameter of 2.8 mm.

[0064] After testing, the hydrogen content of the titanium welding wire prepared in this embodiment is 0.001%, which meets the requirements (the standard requires the hydrogen content to be less than 0.008%), and the diameters of multiple parts of the titanium welding wire are measured, which are 2.802mm, 2.804mm, and 2.802mm respectively, which meet the national standard requirements.

[0065] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent change made to the above embodiment according to the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing titanium welding wire by multi-roller die combined drawing, characterized in that: The method comprises the following steps: Step 1: rounding the titanium rod to obtain a round rod, and then peeling the round rod to obtain a rod to be drawn by a roller die; Step 2, subjecting the rod material to be roller-die-drawn obtained in step 1 to roller-die-drawing for the first time to obtain a primary roller-die-drawn rod material; Step 3, performing a vacuum annealing on the primary roller mold bar obtained in step 2 to obtain a vacuum annealed primary roller mold bar; Step 4: subjecting the vacuum annealed primary roller die bar obtained in step 3 to a second roller die drawing to obtain a secondary roller die bar; Step 5, subjecting the secondary roller die bar obtained in step 4 to a third roller die drawing to obtain a tertiary roller die bar; Step 6: The three-roller die bar obtained in step 5 is subjected to vacuum annealing and then surface polishing to obtain titanium welding wire.

2. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: The diameter of the titanium rod in step one is 8mm~9mm, the rounding deformation in the rounding is 8.7%~9.8%, and the diameter of the rounded rod is 7.6mm~8.6mm; the peeling is carried out using a centerless lathe, the peeling amount is 0.3mm~0.4mm, the diameter of the rod to be drawn by the roller die is 7.2mm~8.2mm, and the surface is bright.

3. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: The first roller die drawing in step 2 is a continuous drawing of four groups of roller dies. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 11.8% to 18.7%, the total deformation is 46.5% to 51.8%, the drawing speed is 80m / min to 100m / min, and the diameter of the first roller die bar is 5.0mm to 6.0mm.

4. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: The vacuum annealing temperature in step 3 is 600° C. to 650° C., and the time is 120 min to 180 min.

5. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: The second roller die drawing described in step four is a continuous drawing of four groups of roller dies. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 9.7% to 19.5%, the total deformation is 38.9% to 51.0%, the drawing speed is 100m / min to 120m / min, and the diameter of the secondary roller die bar is 3.5mm to 4.5mm.

6. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: The third roller die drawing in step five is a continuous drawing of four groups of roller dies. A single group of roller dies is composed of mutually perpendicular horizontal and vertical roller dies. The deformation of each roller die is 12.9% to 27.0%, the total deformation is 54.7% to 65.7%, the drawing speed is 100m / min to 120m / min, and the diameter of the three roller die rods is 2.05mm to 3.05mm.

7. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: The temperature of the finished product vacuum annealing in step six is ​​600°C to 650°C, the time is 120min to 180min, the thickness of the surface polishing is 0.03mm to 0.05mm, and the diameter of the titanium welding wire is 2.0mm to 3.0mm.

8. The method for preparing titanium welding wire by multi-roller die combined drawing according to claim 1 is characterized in that: No heating oxidation or surface coating is required before the first roller die drawing in step 2, the second roller die drawing in step 4, and the third roller die drawing in step 5.