Preparation method of ultralow-hydrogen TA17 titanium alloy welding wire

Abstract

The invention relates to the technical field of wire preparation, and particularly discloses a preparation method of an ultralow-hydrogen TA17 titanium alloy welding wire, which comprises the following steps: S100, preparing a TA17 titanium alloy wire rod through smelting, forging and rolling; s200, the wire rod is subjected to rounding-peeling-polishing process treatment, and a wire rod with the bright surface is obtained; s300, the coiled wire is subjected to multi-pass roller die drawing, and a drawn wire material is obtained; s400, the drawn wire is subjected to online ultrasonic cleaning, and the wire with the clean surface is obtained; s500, the clean-state wire is subjected to vacuum heat treatment, and an annealed-state wire is obtained; and S600, the step S300, the step S400 and the step S500 are repeatedly executed for multiple times, and a finished wire is obtained. According to the method, starting from a wire drawing deformation mode, a heat treatment process and a cleaning process, the diameter of the wire is reduced in a roller die cold drawing mode, so that the problem that the titanium alloy wire easily absorbs hydrogen is solved, the hydrogen content of the TA17 welding wire is reduced, and the quality of the titanium alloy wire is improved.

Description

Technical Field

[0001] The invention relates to the technical field of wire material preparation, and in particular to a method for preparing an ultra-low hydrogen TA17 titanium alloy welding wire. Background Art

[0002] TA17 is a near-α-type ternary titanium alloy mainly composed of aluminum, vanadium and titanium. Its nominal composition is Ti-4Al-2V. Aluminum as an α-stabilizing element can improve the thermal strength of the alloy, and vanadium as a β-stabilizing element can refine the grains and improve plasticity. TA17 has excellent corrosion resistance, high temperature resistance, high fatigue performance and good weldability. Its main products are plates, wire rods and forgings, which are widely used in the preparation of components for large ships. With the acceleration of the promotion of engineering applications of TA17 alloy in the field of shipbuilding, more stringent requirements are placed on the quality stability of supporting welding materials.

[0003] The microstructure of the weld joint determines the mechanical properties of the entire weld. Different hydrogen contents will change the organizational structure and phase composition of the weld joint, thereby affecting the mechanical properties of the titanium alloy weld joint. Moreover, a small amount of hydrogen at room temperature can cause hydrogen embrittlement fracture of titanium alloy welds, and hydrogen embrittlement accidents occur from time to time.

[0004] As a reversible alloying element, hydrogen can reduce the hydrogen content in titanium alloys by heat treatment. According to the method disclosed in the prior art CN111036829B, the hydrogen content of β-titanium alloy wire can be controlled within 0.0008%. However, the preparation method of α-type TA17 titanium alloy welding wire with lower requirements for hydrogen content (≤0.0003%) is not mentioned.

[0005] Therefore, developing a method for preparing ultra-low hydrogen TA17 welding wire is of great significance for reducing the hydrogen embrittlement problem that is easily generated during welding of TA17 plates and promoting the application of TA17 welding wire in the shipbuilding field. Summary of the invention

[0006] In view of the shortcomings of the prior art, the main purpose of the present invention is to provide a method for preparing high-quality ultra-low hydrogen TA17 titanium alloy welding wire. The method starts from the wire drawing deformation method, heat treatment process and cleaning process, and adopts roller die cold drawing to reduce the wire diameter, thereby reducing the problem of titanium alloy wire easily absorbing hydrogen, reducing the hydrogen content of TA17 welding wire, and improving the quality of titanium alloy wire.

[0007] In order to solve at least one of the above technical problems, the present invention adopts the following technical solution: According to the present invention, a method for preparing an ultra-low hydrogen TA17 titanium alloy welding wire is provided, comprising the following steps: S100, preparing a TA17 titanium alloy coil by smelting, forging and rolling; S200, subjecting the coil to a rounding-skinning-polishing process to obtain a coiled wire with a bright surface; S300, subjecting the coiled wire to a plurality of roller die drawing processes to obtain a drawn wire; S400, subjecting the drawn wire to an online ultrasonic cleaning process to obtain a surface-cleaned wire; S500, subjecting the cleaned wire to a vacuum heat treatment process to obtain an annealed wire; S600, repeatedly executing steps S300, S400 and S500 to obtain a finished wire.

[0008] According to one embodiment of the present invention, in step S100, three vacuum consumable smelting processes are performed to obtain a TA17 ingot, and a Φ8.5 mm titanium alloy disc is obtained by forging and rolling.

[0009] According to one embodiment of the present invention, the TA17 titanium alloy disc is composed of the following chemical components in weight percentage: Al: 3.5wt%~4.5wt%, V: 1.5wt%~2.5wt%, Fe≤0.05wt%, C≤0.02wt%, H≤0.005wt%, O≤0.05wt%, N≤0.03wt%, Si≤0.01wt%, and the balance is Ti and unavoidable impurities.

[0010] According to one embodiment of the present invention, step S200 includes: S210, performing room temperature rotary forging on the titanium alloy disc by rotary forging, controlling the rotary forging speed to 5~10m / min, the rotary forging deformation to 10%~12%, and the lubricant to be industrial lubricating oil; S220, performing skinning on the disc after rotary forging by turning, controlling the spindle speed to 1000~1200r / min, the skinning speed to 5~7m / min, the linear speed to 28~30m / min, and the skinning amount to 0.4~0.6mm; S230, polishing the skinned disc by a sand belt polisher, controlling the sand belt mesh number to 240 mesh, 320 mesh, and 480 mesh, the polishing speed to 5~7m / min, the polishing frequency to 20~25Hz, and the polishing amount to 0.01~0.02mm.

[0011] According to an embodiment of the present invention, in step S300, the drawing equipment is a six-pass continuous cold drawing machine, and six sets of dies are installed at the same time for drawing; the roller die has a two-roller symmetrical structure, consisting of five sets of rollers. The five sets of rollers are arranged in a horizontal + vertical + horizontal + vertical + horizontal manner, the first three sets of rollers are deformation rollers, and the last two sets of rollers are shaping rollers.

[0012] According to an embodiment of the present invention, in step S300, a water-soluble lubricant is used for lubrication during roller die drawing, wherein the water-soluble lubricant is composed of the following chemical components in weight percentage: 30% to 50% thioene, 3% to 5% sorbitan monooleate, 1% to 5% carboxylic acid ether, 0.1% to 1% bactericide, and the rest is deionized water.

[0013] According to one embodiment of the present invention, in step S300, the wire outlet accuracy of each pass is controlled to be within ±0.02mm, the drawing speed is 60-90m / min, the deformation of a single drawing pass is about 12%, and the coiled wire is annealed and heat treated after each cumulative diameter reduction of 3-4 times, and the cumulative deformation is controlled to be 40%-50% to obtain a drawn wire.

[0014] According to one embodiment of the present invention, in step S400, the online ultrasonic cleaning equipment includes 4 ultrasonic cleaning tanks and 1 drying tank, wherein the first 3 cleaning tanks contain weak alkaline cleaning agents and the 4th cleaning tank contains clean water; during the online ultrasonic cleaning process, the ultrasonic frequency is controlled to be 80~100kHz, the cleaning tank medium temperature is 50~60℃, the travel speed is 5~10m / min; and the drying temperature is 120~150℃.

[0015] According to one embodiment of the present invention, in step S500, the vacuum heat treatment adopts a horizontal vacuum resistance furnace, and the working vacuum degree is controlled to be less than 9×10 -4 Pa, pressure rise rate ≤ 0.1Pa / h, heating element is molybdenum-lanthanum alloy belt, and heat shield contains multiple layers of high-temperature molybdenum shield. During vacuum heat treatment, control the temperature to 500℃ in 60min, keep warm for 30min, then heat to 720~750℃ in 60min, keep warm for 180~240min, and finally cool to 400℃ and fill with 99.999% high-purity argon for rapid cooling, wait for the temperature in the furnace to drop to 50℃, wait for natural cooling for 120~150min before taking out of the furnace.

[0016] According to an embodiment of the present invention, in step S600, step S300, step S400 and step S500 are performed at least three times to obtain the finished wire material.

[0017] By adopting the above technical solution, the present invention has at least one of the following advantages compared with the prior art: (1) The present invention starts from the wire drawing deformation mode, adopts the roller die cold drawing method to reduce the wire diameter, and the whole process is cold processed. The wire will not absorb hydrogen in the air, thereby achieving the purpose of not increasing the hydrogen content during the drawing process.

[0018] (2) The present invention uses a water-soluble lubricant, which has low adhesion and dissolves immediately in water, making it convenient to clean the residual lubricant on the surface of the wire by subsequent online ultrasonic cleaning. In addition, the dryer can effectively remove moisture from the surface of the wire to prevent hydrogenation during the heat treatment process.

[0019] (3) The present invention adopts online ultrasonic cleaning. Compared with offline cleaning, online cleaning can ensure the uniformity of cleaning the surface of the wire material and ensure that the wire material can achieve a clean and pollution-free surface state during vacuum heat treatment, thereby achieving the purpose of not increasing the hydrogen content during vacuum heat treatment.

[0020] (4) The present invention adopts a special vacuum resistance furnace with extremely low working vacuum degree and pressure rise rate, and the multi-layer molybdenum screen can prevent the adhesion of pollutants, which is beneficial to the cleanliness of the vacuum system. At the same time, the heat treatment process can also ensure that hydrogen can be fully released from the wire, thereby achieving the purpose of reducing the hydrogen content.

[0021] (5) The full-process technology adopted in the present invention can reduce the hydrogen content to less than 0.0003%. Compared with conventional dehydrogenation treatment, the hydrogen content of this method is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 Schematic diagram of the steps of a method for preparing an ultra-low hydrogen TA17 titanium alloy welding wire according to an embodiment of the present invention; Figure 2 The microstructure diagram of the TA17 titanium alloy wire rod of Φ8.5 mm in accordance with the present invention; Figure 3 This is a microstructure diagram of a TA17 titanium alloy welding wire with a specification of Φ3.0 mm according to Example 1 of the present invention; Figure 4 This is a microstructure diagram of a TA17 titanium alloy welding wire with a specification of Φ2.0 mm according to Example 2 of the present invention; Figure 5 This is a microstructure diagram of a TA17 titanium alloy welding wire with a diameter of Φ3.0 mm according to Comparative Example 1 of the present invention; Figure 6 This is a microstructure diagram of a TA17 titanium alloy welding wire with a specification of Φ3.0 mm according to comparative example 2 of the present invention. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0025] It should be understood that the embodiments of the present invention shown in the exemplary embodiments are only illustrative. Although only a few embodiments are described in detail in the present invention, it is easy for those skilled in the art to appreciate that multiple modifications are feasible without actually departing from the teaching of the subject matter of the present invention. Accordingly, all such modifications should be included within the scope of the present invention. Without departing from the gist of the present invention, other replacements, modifications, changes and deletions may be made to the design, operating conditions and parameters of the following exemplary embodiments.

[0026] The present invention provides a method for preparing ultra-low hydrogen TA17 titanium alloy welding wire. Figure 1 As shown, the method generally comprises the following steps: S100, TA17 titanium alloy disc is prepared by melting, forging and rolling; S200, performing a process of rounding, peeling and polishing on the coiled wire to obtain a coiled wire with a bright surface; S300, performing multiple roller die drawing on the coiled wire to obtain a drawn wire material; S400, performing online ultrasonic cleaning on the drawn wire to obtain a surface-cleaned wire; S500, performing vacuum heat treatment on the clean wire to obtain an annealed wire; S600, repeatedly executing step S300, step S400 and step S500 to obtain a finished wire material.

[0027] Step S100 can obtain TA17 ingots by three vacuum consumable smeltings, and obtain Φ8.5mm titanium alloy discs by forging and rolling. In an embodiment of the present invention, the TA17 titanium alloy discs are composed of the following chemical components in weight percentage: Al: 3.5wt%~4.5wt%, V: 1.5wt%~2.5wt%, Fe≤0.05wt%, C≤0.02wt%, H≤0.005wt%, O≤0.05wt%, N≤0.03wt%, Si≤0.01wt%, and the remainder is Ti and unavoidable impurities. In other embodiments, those skilled in the art can use the teachings disclosed herein to seek to obtain the desired properties and appropriately change the values ​​of each element. It should be understood that the use of numerical ranges represented by endpoints includes all numbers within the range and any range within the range. Taking Al as an example, 3.5wt%~4.5wt% may include 3.5wt%, 4.0wt%, 4.5wt%, and so on. The microstructure of the prepared TA17 titanium alloy disk is an α single-phase equiaxed microstructure, and the average α grain size is preferably ≤15 μm. The specific microstructure is as shown in the attached Figure 2 shown.

[0028] In step S200, before cold drawing, the TA17 titanium alloy coil obtained in step S100 is subjected to rotary forging, peeling and polishing to obtain a coiled wire with a bright surface, which may specifically include: S210, the titanium alloy disc is forged at room temperature by rotary forging, the rotary forging speed is controlled to be 5-10 m / min, the rotary forging deformation is 10%-12%, and the lubricant is industrial lubricating oil; S220, the disc after rotary forging is peeled by turning, the spindle speed is controlled to be 1000~1200r / min, the peeling speed is 5~7m / min, the line speed is 28~30m / min, and the peeling amount is 0.4~0.6mm; S230, use a sand belt polisher to polish the peeled disc, control the sand belt mesh number to 240 mesh, 320 mesh, 480 mesh, polishing speed to 5~7m / min, polishing frequency to 20~25Hz, polishing amount to 0.01~0.02mm.

[0029] In step S300, the specific drawing equipment can be a six-pass continuous cold drawing machine, and six groups of dies are installed at the same time for drawing; the wheel type of the roller die is a two-roller symmetrical structure, consisting of five groups of rollers. Among them, the five groups of rollers are preferably arranged in a horizontal + vertical + horizontal + vertical + horizontal manner, the first three groups of rollers are deformation rollers, and the last two groups of rollers are shaping rollers. In an embodiment of the present invention, the accuracy of the wire outlet of each pass is specifically controlled to be within ±0.02mm, the drawing speed is 60~90m / min, the deformation amount of a single drawing pass is about 12%, and the coiled wire is annealed and heat treated after each cumulative diameter reduction of 3~4 times, and the cumulative deformation amount is controlled to be 40%~50% to obtain a drawn wire. During the roller die drawing process, a water-soluble lubricant can be used for lubrication. The water-soluble lubricant is preferably composed of the following chemical components in weight percentage: 30% to 50% thioene, 3% to 5% sorbitan monooleate, 1% to 5% carboxylic acid ether, 0.1% to 1% bactericide, and the rest is deionized water.

[0030] In step S400, the drawn wire is cleaned of the lubricant on the surface of the wire by online ultrasonic cleaning before vacuum heat treatment. In an embodiment of the present invention, the online ultrasonic cleaning equipment includes 4 ultrasonic cleaning tanks and 1 drying tank. The first 3 cleaning tanks contain weak alkaline cleaning agents, and the 4th cleaning tank contains clean water. During the online ultrasonic cleaning process, it is preferred to control the ultrasonic frequency to 80~100kHz, the cleaning tank medium temperature to 50~60℃, and the travel speed to 5~10m / min. The drying temperature is 120~150℃.

[0031] In step S500, the clean wire obtained in step S400 is subjected to vacuum heat treatment to obtain an annealed wire. Specifically, a horizontal vacuum resistance furnace can be used for vacuum heat treatment, and the working vacuum degree is preferably controlled to be less than 9×10 -4 Pa, pressure rise rate ≤ 0.1Pa / h, the heating element is a molybdenum-lanthanum alloy strip, and the heat insulation screen includes multiple layers of high-temperature molybdenum screens. In an embodiment of the present invention, the number of metal reflective screens used in the heat insulation screen is 5 layers, which are configured from the inside to the outside as follows: 3 layers of high-temperature molybdenum screens, and the rest are 2 layers of stainless steel screens. The molybdenum screen can be mirror polished, and the working material rack is a molybdenum grid material tray. During the vacuum heat treatment process, it is preferably controlled to heat up to 500°C in 60 minutes, keep warm for 30 minutes, then heat up to 720~750°C in 60 minutes, keep warm for 180~240 minutes, and finally cool to 400°C and fill with 99.999% high-purity argon for rapid cooling. When the temperature in the furnace drops to 50°C, wait for natural cooling for 120~150 minutes before taking out of the furnace.

[0032] In step S600, steps S300, S400 and S500 are repeatedly performed to obtain finished wire. In an embodiment of the present invention, steps S300, S400 and S500 need to be repeated at least 3 times, and finally the Φ8.5 mm coil is drawn into a finished wire of Φ3.0-Φ1.6 mm.

[0033] The following are specific embodiments of the ultra-low hydrogen TA17 titanium alloy wire and the preparation method thereof according to the present invention and their specific process parameters.

[0034] Example 1 Φ3.0mm TA17 titanium alloy wire is prepared using Φ8.5mm TA17 titanium alloy coil.

[0035] Step 100: Prepare TA17 titanium alloy disc by smelting, forging and rolling. Specifically, three vacuum consumable smeltings are used to obtain TA17 ingots, and Φ8.5mm titanium alloy discs are obtained by forging and rolling. The composition of TA17 titanium alloy discs is as follows: Al: 5.6wt%, V: 3.9wt%, Fe: 0.025wt%, C: 0.012wt%, H: 0.0045wt%, O: 0.045wt%, N: 0.0025wt%, Si: 0.005wt%, and the remainder is Ti and unavoidable impurities.

[0036] Step 200: Perform the process of rotary forging, peeling and polishing on the disc produced in step 100. Specifically, Step 210: Forging the titanium alloy disc at room temperature by rotary forging, with a rotary forging speed of 5 m / min, a rotary forging deformation of 10%, an industrial lubricating oil as lubricant, and a size of Φ8.0 mm±0.05 mm after rotary forging; Step 220: peeling the disc after rotary forging by turning, with a turning tool speed of 1000 r / min, a peeling speed of 5 m / min, a linear speed of 28 m / min, a peeling amount of 0.4 mm, and a size of Φ7.6 mm±0.05 mm after peeling; Step 230: Use a sand belt polisher to polish the peeled disc, the sand belt mesh size is 240 mesh and 320 mesh, the polishing speed is 5m / min, the polishing frequency is 20Hz, and the polishing amount is 0.01mm.

[0037] Step 300: evenly apply a water-soluble lubricant to the bright wire obtained in step 200, and then perform roller die drawing.

[0038] The water-soluble lubricant is mainly composed of 30% thioene, 5% sorbitan monooleate, 5% carboxylic acid ether, 1% bactericide, and the rest is deionized water.

[0039] Among them, during roller die drawing, the wire outlet accuracy of each pass needs to be controlled within ±0.02mm, the drawing speed is 60m / min, and annealing heat treatment is performed after each cumulative diameter reduction of 3 times during drawing. The cumulative deformation is controlled to 40% to obtain a drawn Φ6.5mm wire.

[0040] Step 400: performing online ultrasonic cleaning on the drawn wire obtained in step 300.

[0041] The ultrasonic frequency is 80kHz, the medium temperature of the cleaning tank is 50°C, the travel speed is 5m / min, and the drying temperature is 120°C.

[0042] Step 500: The wire cleaned in step 400 is subjected to vacuum heat treatment to obtain annealed wire. During vacuum heat treatment, the temperature is raised to 500°C for 60 minutes, kept at this temperature for 30 minutes, then raised to 720°C for 60 minutes, kept at this temperature for 180 minutes, and finally cooled to 400°C and filled with 99.999% high-purity argon gas for rapid cooling. When the temperature in the furnace drops to 50°C, the wire is taken out of the furnace after natural cooling for 120 minutes.

[0043] Step 600: Repeat steps 300, 400 and 500 twice for the annealed wire prepared in step 500 to obtain an annealed wire with a diameter of 3.0 mm.

[0044] The microstructure of the TA17 welding wire with a diameter of Φ3.0 mm prepared in this embodiment was observed, and the microstructure results are as follows: Figure 3As shown, its grains are uniform and small. The prepared Φ3.0mm TA17 wire was tested for harmful elements. Six test points (six test points were selected separately) were selected from the prepared TA17 welding wire to test C, H, O, and N elements. The results are shown in Table 1. It can be seen from Table 1 that the C, O, and N element contents of the wire did not increase, and the H content was not more than 0.0003wt%.

[0045] Table 1 Chemical element test results of Φ3.0mm annealed TA17 wire

[0046] Example 2 Φ2.0mm TA17 titanium alloy wire is prepared using Φ8.5mm TA17 titanium alloy coil.

[0047] Step 100: Prepare TA17 titanium alloy disc by smelting, forging and rolling. Specifically, three vacuum consumable smeltings are used to obtain TA17 ingots, and Φ8.5mm titanium alloy discs are obtained by forging and rolling. The composition of TA17 titanium alloy discs is as follows: Al: 5.7wt%, V: 4.0wt%, Fe: 0.030wt%, C: 0.014wt%, H: 0.0041wt%, O: 0.039wt%, N: 0.0021wt%, Si: 0.006wt%, and the remainder is Ti and unavoidable impurities.

[0048] Step 200: Perform the process of rotary forging, peeling and polishing on the disc produced in step 100. Specifically, Step 210: performing rotary forging of the titanium alloy disc at room temperature by rotary forging, the rotary forging speed is 6 m / min, the rotary forging deformation is 11%, the lubricant is industrial lubricating oil, and the size after rotary forging is Φ8.0 mm±0.05 mm; Step 220: peeling the disc after rotary forging by turning, with a turning tool speed of 1100 r / min, a peeling speed of 6 m / min, a linear speed of 30 m / min, a peeling amount of 0.5 mm, and a size of Φ7.5 mm±0.05 mm after peeling; Step 230: Use a sand belt polisher to polish the peeled disc, the sand belt mesh size is 240 mesh and 320 mesh, the polishing speed is 6m / min, the polishing frequency is 23Hz, and the polishing amount is 0.015mm.

[0049] Step 300: evenly apply a water-soluble lubricant to the bright wire obtained in step 200, and then perform roller die drawing.

[0050] The water-soluble lubricant is mainly composed of 40% thioene, 3% sorbitan monooleate, 3% carboxylic acid ether, 0.8% bactericide, and the rest is deionized water.

[0051] Among them, during roller die drawing, the wire outlet accuracy of each pass needs to be controlled within ±0.02mm, the drawing speed is 80m / min, and annealing heat treatment is performed after each cumulative diameter reduction of 3 times during drawing. The cumulative deformation is controlled to 40% to obtain a drawn Φ6.5mm wire.

[0052] Step 400: performing online ultrasonic cleaning on the drawn wire obtained in step 300.

[0053] The ultrasonic frequency is 90kHz, the medium temperature of the cleaning tank is 55°C, the travel speed is 6m / min, and the drying temperature is 130°C.

[0054] Step 500: The wire cleaned in step 400 is subjected to vacuum heat treatment to obtain annealed wire. During vacuum heat treatment, the temperature is raised to 500°C for 60 minutes, kept at this temperature for 30 minutes, then raised to 730°C for 60 minutes, kept at this temperature for 200 minutes, and finally cooled to 400°C and filled with 99.999% high-purity argon gas for rapid cooling. When the temperature in the furnace drops to 50°C, the wire is taken out of the furnace after natural cooling for 130 minutes.

[0055] Step 600: Repeat steps 300, 400 and 500 three times to obtain an annealed wire of Φ2.0 mm. The microstructure of the TA17 welding wire with a diameter of Φ2.0 mm prepared in this embodiment was observed. The microstructure results are as follows: Figure 4 As shown, its grains are uniform and small. The prepared Φ2.0mm TA17 wire was tested for harmful elements. Six test points (six test points were selected separately) were selected from the prepared TA17 welding wire to test C, H, O, and N elements. The results are shown in Table 2. It can be seen from Table 2 that the C, O, and N element contents of the wire did not increase, and the H content was not more than 0.0003wt%.

[0056] Table 2 Chemical element test results of Φ2.0mm annealed TA17 wire

[0057] It can be seen from the above embodiments that the TA17 welding wire prepared by the present invention has a simple process. After multiple processing steps, not only the content of harmful elements C, N, and O in the wire can be effectively controlled, but also the H content of the wire can be greatly reduced to below 0.0003wt%, thereby preparing an ultra-low hydrogen TA17 welding wire.

[0058] Comparative Example 1 This comparative example adopts cold drawing to prepare Φ3.0 mm TA17 titanium alloy wire. The preparation process is the same as that of Example 1, except that the lubricant in step 300 is replaced with an oil lubricant, and the vacuum heat treatment furnace in step 500 is of conventional design.

[0059] Step 100: Prepare TA17 titanium alloy disc by smelting, forging and rolling.

[0060] Specifically, TA17 ingots were obtained by three vacuum consumable smelting processes, and Φ8.5 mm titanium alloy discs were obtained by forging and rolling. The composition of the TA17 titanium alloy discs is as follows: Al: 5.8 wt%, V: 4.1 wt%, Fe: 0.030 wt%, C: 0.012 wt%, H: 0.0040 wt%, O: 0.040 wt%, N: 0.0020 wt%, Si: 0.006 wt%, and the balance is Ti and unavoidable impurities.

[0061] Step 200: The coil of step 100 is subjected to a process of rotary forging, peeling and polishing. Specifically, Step 210: performing rotary forging of the titanium alloy disc at room temperature by rotary forging, the rotary forging speed is 6 m / min, the rotary forging deformation is 11%, the lubricant is industrial lubricating oil, and the size after rotary forging is Φ8.0 mm±0.05 mm; Step 220: peeling the disc after rotary forging by turning, with a turning tool speed of 1100 r / min, a peeling speed of 6 m / min, a linear speed of 30 m / min, a peeling amount of 0.5 mm, and a size of Φ7.5 mm±0.05 mm after peeling; Step 230: Use a sand belt polisher to polish the peeled disc, the sand belt mesh size is 240 mesh and 320 mesh, the polishing speed is 6m / min, the polishing frequency is 23Hz, and the polishing amount is 0.015mm.

[0062] Step 300: Evenly apply an oil lubricant to the bright wire obtained in step 200, and then perform roller die drawing.

[0063] Among them, during roller die drawing, the wire outlet accuracy of each pass needs to be controlled within ±0.02mm, the drawing speed is 80m / min, and annealing heat treatment is performed after each cumulative diameter reduction of 3 times during drawing. The cumulative deformation is controlled to 40% to obtain a drawn Φ6.5mm wire.

[0064] Step 400: performing online ultrasonic cleaning on the drawn wire obtained in step 300.

[0065] The ultrasonic frequency is 90kHz, the medium temperature of the cleaning tank is 55°C, the travel speed is 6m / min, and the drying temperature is 130°C.

[0066] Step 500: The wire material cleaned in step 400 is subjected to vacuum heat treatment to obtain an annealed wire material. The vacuum heat treatment is performed using a conventional horizontal vacuum resistance furnace with a working vacuum degree of <6×10 -3 Pa, pressure rise rate ≤ 0.3Pa / h, heating element is nickel-chromium alloy strip. The heat insulation screen adopts 5 layers of non-full metal reflective screen, which are configured from inside to outside: 3 layers of high-temperature nickel screen and the rest are 2 layers of ceramic screen.

[0067] During vacuum heat treatment, the temperature is raised to 500°C in 60 minutes, kept at this temperature for 30 minutes, then raised to 730°C in 60 minutes, kept at this temperature for 200 minutes, and finally cooled to 400°C and filled with 99.999% high-purity argon for rapid cooling. When the temperature in the furnace drops to 50°C, wait for natural cooling for 130 minutes before taking out of the furnace.

[0068] Step 600: Repeat steps 300, 400 and 500 twice for the annealed wire prepared in step 500 to obtain an annealed wire with a diameter of 3.0 mm.

[0069] The microstructure of the TA17 welding wire with a diameter of Φ3.0 mm prepared in this comparative example was observed. The microstructure results are as follows: Figure 5 As shown, its grains are uniform and small. The prepared Φ3.0mm TA17 wire was tested for harmful elements. Six test points (six test points were selected separately) were selected from the prepared TA17 welding wire to test C, H, O, and N elements. The results are shown in Table 3. It can be seen from Table 3 that the C, O, and N content of the wire increased slightly, and although the H content decreased, it could only be controlled within 0.0013wt%.

[0070] Table 3 Chemical element test results of Φ3.0mm annealed TA17 wire

[0071] Comparative Example 2 In this comparative example, a 3.0 mm TA17 titanium alloy wire is prepared by hot drawing. The preparation process is the same as that of Example 1, except that the roller die drawing in step 300 is replaced by hot drawing.

[0072] Step 100: Prepare TA17 titanium alloy disc by smelting, forging and rolling.

[0073] Specifically, TA17 ingots were obtained by three vacuum consumable smelting processes, and Φ8.5 mm titanium alloy discs were obtained by forging and rolling. The composition of the TA17 titanium alloy discs is as follows: Al: 5.8 wt%, V: 4.1 wt%, Fe: 0.030 wt%, C: 0.012 wt%, H: 0.0040 wt%, O: 0.040 wt%, N: 0.0020 wt%, Si: 0.006 wt%, and the remainder is Ti and unavoidable impurities.

[0074] Step 200: The coil of step 100 is subjected to a process of rotary forging, peeling and polishing. Specifically, Step 210: Forging the titanium alloy disc at room temperature by rotary forging, with a rotary forging speed of 5 m / min, a rotary forging deformation of 10%, an industrial lubricating oil as lubricant, and a size of Φ8.0 mm±0.05 mm after rotary forging; Step 220: peeling the disc after rotary forging by turning, with a turning tool speed of 1000 r / min, a peeling speed of 5 m / min, a linear speed of 28 m / min, a peeling amount of 0.4 mm, and a size of Φ7.6 mm±0.05 mm after peeling; Step 230: Use a sand belt polisher to polish the peeled disc, the sand belt mesh size is 240 mesh and 320 mesh, the polishing speed is 5m / min, the polishing frequency is 20Hz, and the polishing amount is 0.01mm.

[0075] Step 300: The intermediate wire obtained in step 200 is reduced in diameter by hot drawing, with a heating temperature of 820°C, a drawing speed of 10 m / min, and graphite emulsion as a drawing lubricant. The diameter is reduced to Φ3.0 mm through 13 passes.

[0076] Step 400: The wire material after heat drawing in step 300 is subjected to vacuum heat treatment. The vacuum heat treatment adopts a horizontal vacuum resistance furnace with a working vacuum degree of <9×10 -4 Pa, pressure rise rate ≤0.1Pa / h, heating element is molybdenum-lanthanum alloy strip. The heat insulation screen uses 5 layers of metal reflective screen, which are configured from inside to outside: 3 layers of high-temperature molybdenum screen and the rest are 2 layers of stainless steel screen. The molybdenum screen is mirror polished. The working material rack is a molybdenum grid material tray.

[0077] During vacuum heat treatment, the temperature is raised to 500°C in 60 minutes, kept at this temperature for 30 minutes, then raised to 730°C in 60 minutes, kept at this temperature for 200 minutes, and finally cooled to 400°C and filled with 99.999% high-purity argon for rapid cooling. When the temperature in the furnace drops to 50°C, wait for natural cooling for 130 minutes before taking out of the furnace.

[0078] The microstructure of the TA17 welding wire with a diameter of Φ3.0 mm prepared in this comparative example was observed. The microstructure results are as follows: Figure 6 As shown, its structure is mainly α equiaxed crystal. The prepared Φ3.0mm TA17 wire was tested for harmful elements. Six test points (six test points were selected separately) were selected from the prepared TA17 welding wire to test C, H, O, and N elements. The results are shown in Table 4. It can be seen from Table 4 that the C, O, and N content of the wire increased, and the H content decreased but remained at about 0.0030wt%.

[0079] Table 4 Chemical element test results of Φ3.0mm annealed TA17 wire

[0080] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. If the present invention is modified or replaced by equivalents without departing from the spirit and scope of the present invention, it should be included in the protection scope of the present invention.

[0081] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention is limited to these examples; under the idea of ​​the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for preparing ultra-low hydrogen TA17 titanium alloy welding wire, characterized in that: The following steps are involved: S100, TA17 titanium alloy disc is prepared by melting, forging and rolling; S200, performing a process of rounding, peeling and polishing on the coiled wire to obtain a coiled wire with a bright surface; S300, performing multiple roller die drawing on the coiled wire to obtain a drawn wire material; S400, performing online ultrasonic cleaning on the drawn wire to obtain a surface-cleaned wire; S500, performing vacuum heat treatment on the clean wire to obtain an annealed wire; S600, repeatedly executing step S300, step S400 and step S500 to obtain a finished wire material.

2. The method according to claim 1, characterized in that In step S100, The TA17 ingot was obtained by three vacuum consumable melting processes, and the Φ8.5 mm titanium alloy disc was obtained by forging and rolling.

3. The method according to claim 2, characterized in that The TA17 titanium alloy disc is composed of the following chemical components in weight percentage: Al: 3.5wt%~4.5wt%, V: 1.5wt%~2.5wt%, Fe≤0.05wt%, C≤0.02wt%, H≤0.005wt%, O≤0.05wt%, N≤0.03wt%, Si≤0.01wt%, and the balance is Ti and unavoidable impurities.

4. The method according to claim 1, characterized in that: Step S200 includes: S210, the titanium alloy disc is forged at room temperature by rotary forging, the rotary forging speed is controlled to be 5-10 m / min, the rotary forging deformation is 10%-12%, and the lubricant is industrial lubricating oil; S220, the disc after rotary forging is peeled by turning, the spindle speed is controlled to be 1000~1200r / min, the peeling speed is 5~7m / min, the line speed is 28~30m / min, and the peeling amount is 0.4~0.6mm; S230, use a sand belt polisher to polish the peeled disc, control the sand belt mesh number to 240 mesh, 320 mesh, 480 mesh, polishing speed to 5~7m / min, polishing frequency to 20~25Hz, polishing amount to 0.01~0.02mm.

5. The method according to claim 1, characterized in that In step S300, The drawing equipment is a six-pass continuous cold drawing machine, with six sets of dies installed for drawing at the same time; The roller mold has a two-roller symmetrical structure, consisting of five sets of rollers; Among them, the five groups of rollers are arranged in a horizontal + vertical + horizontal + vertical + horizontal manner, the first three groups of rollers are deforming rollers, and the last two groups of rollers are shaping rollers.

6. The method according to claim 5, characterized in that In step S300, a water-soluble lubricant is used for lubrication during roller die drawing; The water-soluble lubricant is composed of the following chemical components in weight percentage: 30% to 50% of thioene, 3% to 5% of sorbitan monooleate, 1% to 5% of carboxylic acid ether, 0.1% to 1% of bactericide, and the rest is deionized water.

7. The method according to claim 5, characterized in that In step S300, the wire outlet accuracy of each pass is controlled within ±0.02mm, the drawing speed is 60-90m / min, the deformation of a single drawing pass is about 12%, and the coiled wire is annealed and heat treated after 3-4 cumulative diameter reductions, and the cumulative deformation is controlled to be 40%-50% to obtain a drawn wire.

8. The method according to claim 1, characterized in that In step S400, The online ultrasonic cleaning equipment includes 4 ultrasonic cleaning tanks and 1 drying tank. The first 3 cleaning tanks contain weak alkaline cleaning agents, and the 4th cleaning tank contains clean water. During the online ultrasonic cleaning process, the ultrasonic frequency is controlled at 80~100kHz, the medium temperature of the cleaning tank is 50~60℃, the travel speed is 5~10m / min; and the drying temperature is 120~150℃.

9. The method according to claim 1, characterized in that: In step S500, Vacuum heat treatment uses a horizontal vacuum resistance furnace, and the working vacuum degree is controlled to be less than 9×10 -4 Pa, pressure rise rate ≤ 0.1Pa / h, the heating element is a molybdenum-lanthanum alloy strip, and the heat insulation screen contains multiple layers of high-temperature molybdenum screens; During vacuum heat treatment, control the temperature to 500℃ in 60min, keep it warm for 30min, then heat it to 720~750℃ in 60min, keep it warm for 180~240min, and finally cool it to 400℃ and fill it with 99.999% high-purity argon for rapid cooling. When the temperature in the furnace drops to 50℃, wait for natural cooling for 120~150min before taking it out of the furnace.

10. The method according to claim 9, characterized in that In step S600, step S300, step S400 and step S500 are performed at least three times to obtain a finished wire material.

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