A rolling method for cold continuous rolling of titanium and titanium alloy wire

Abstract

The present invention belongs to the technical field of titanium alloy wire processing, and specifically relates to a rolling method for cold tandem rolling of titanium and titanium alloy wires. The present invention designs a ten-sided hole profile for reducing the diameter of titanium and titanium alloy wires. This hole profile is insensitive to roller wear and is suitable for large-scale continuous rolling. Compared with hexagonal or octagonal hole profiles, no folding occurs during the rounding process, and the forming process is easy to control. By designing a smaller deformation amount for the rounding hole profile, the metal flow after rolling is controlled, thereby ensuring the dimensional accuracy of the titanium and titanium alloy wires. The present invention designs a ten-sided hole profile for reducing the diameter and a circular hole profile for rounding, and uses them to produce a series of hole profile rollers. The series of hole profile rollers are further arranged horizontally and vertically in a cold tandem rolling mill. Through high-speed continuous rolling, high-precision titanium and titanium alloy wires are obtained. The cold tandem rolling mill used in the rolling method of the present invention is compact and occupies a small workshop area. It has significant cost and efficiency advantages in the high-speed rolling forming of cold-processed titanium and titanium alloy wires.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium alloy wire processing, and in particular relates to a cold continuous rolling method for titanium and titanium alloy wires. Background Art

[0002] With the development of titanium alloy wire forming technology, wire forming technology with high efficiency, high surface quality and high precision requirements has become the development direction. Existing wire rolling usually adopts fixed die cold drawing or roller die cold drawing, and further combines intermediate vacuum or atmospheric annealing to produce pure titanium, TB9, TB14, Ti15Mo, TC16 and other wires; among them, fixed die cold drawing requires lubricant, and roller die cold drawing usually adopts elliptical-circular hole type. Efficient production requires multiple cold drawing machines or continuous drawing machines, and it is difficult to stably control the dimensional deviation of the finished wire within 0.02mm using the above technology. Therefore, the present invention adopts a compact cold rolling mill, and through the innovative design of the continuous rolling hole type and deformation amount, it can be applied to the high-efficiency rolling forming of titanium and titanium alloy wires. Summary of the Invention

[0003] The object of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a rolling method for continuous cold rolling of titanium and titanium alloy wires.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention provides a method for cold continuous rolling of titanium and titanium alloy wires, comprising the following steps:

[0006] Step 1, hole design: design a hole series for cold rolling reducing of titanium and titanium alloy wire to be processed and a hole series for gauging (hole series for gauging finished products); the hole profiles of the hole series for reducing the diameter are all ten-sided hole profiles, the deformation amount of the reducing pass is 11%~17.5%, the central angle β corresponding to each face of the ten-sided hole profile is 36°, and the chamfer radius γ of the groove bottom of the ten-sided hole profile is 0.8mm~1.2mm; the chamfer R of the ten-sided hole profile is (1 / 4~1 / 3)d0, where d0 is the diameter of the circle of the cross-sectional area of ​​the ten-sided wire; the hole series for gauging the diameter adopts a circular hole profile with gradually increasing precision and gradually decreasing deformation amount, the expansion angle of the circular hole profile is 15°~25°, and the deformation amount of the gauging pass is 2%~8%.

[0007] Step 2, roll production: using an optical curve grinder to respectively produce a series of hole profiles for reducing and a series of hole profiles for calibrating on different rolls, thereby obtaining a series of rolls with hole profiles for reducing and a series of rolls with hole profiles for calibrating; the rolls are made of cold-working die steel such as Cr12MoV, SKD11, DC53, and have an HRC hardness of ≥63; the optical path system magnification of the optical curve grinder is 50 times, and the material of the grinding wheel during roll grinding is selected from white corundum, brown corundum, or diamond to ensure that the deviation between the grinding reference and the center line of the hole profile is less than 0.001 mm, and the grinding accuracy is less than 0.003 mm.

[0008] Step 3, cold rolling: first, the groove series rollers for reducing the diameter and the groove series rollers for gauging the round are respectively installed on the cold rolling mill, and a horizontal-vertical arrangement is adopted. Then, the titanium and titanium alloy wire to be processed are sequentially cold rolled using the groove series rollers for reducing the diameter and the groove series rollers for gauging the round. According to the different cold working properties of titanium and titanium alloys, some materials also need to match vacuum annealing or atmosphere protection online annealing. During the cold rolling process, the groove series rollers for reducing the diameter and the groove series rollers for gauging the round are immersed in rolling oil. The cold rolling speed is 10m / min~100m / min, and the desired titanium and titanium alloy wires are finally obtained.

[0009] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0010] The present invention designs a decagonal hole profile for reducing the diameter of titanium and titanium alloy wire. Compared to a dodecagonal hole profile, this hole profile is less sensitive to roller wear and is suitable for large-scale continuous rolling. Compared to hexagonal or octagonal hole profiles, it does not produce folding during the rounding process, making the forming process easier to control. Furthermore, by designing a smaller deformation for the rounding hole profile, the metal flow after rolling is controlled, thereby ensuring the dimensional accuracy of the titanium and titanium alloy wire. The present invention designs a decagonal hole profile for reducing the diameter and a circular hole profile for rounding the round, and uses these to produce a series of hole profile rollers. Using a compact cold rolling mill, the series of hole profile rollers are further arranged horizontally and vertically within the cold rolling mill. Through high-speed continuous rolling, high-precision titanium and titanium alloy wire is produced. Compared to traditional wire drawing processes, this wire rolling method significantly improves the processing efficiency of titanium and titanium alloy wire and can ensure that the wire's out-of-roundness is within 0.02 mm under high-speed rolling conditions. The cold rolling mill used in the rolling method of the present invention is compact and occupies a small workshop area, and has significant cost and efficiency advantages in high-speed rolling forming of cold-processed titanium and titanium alloy wires. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the invention.

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0013] Figure 1 is a flow chart of the rolling method of the present invention;

[0014] Figure 2 This is the ten-square pass pattern for cold continuous rolling reducing of the present invention;

[0015] Figure 3 This is the hole pattern for the cold rolling gauge of the present invention. DETAILED DESCRIPTION

[0016] Exemplary embodiments will now be described in detail, with examples shown in the accompanying drawings. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present invention. Instead, they are merely examples consistent with some aspects of the present invention as detailed in the appended claims.

[0017] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0018] The present invention provides a method for cold continuous rolling of titanium and titanium alloy wires. Figure 1-3 As shown, the following steps are included:

[0019] Step 1, hole design: design a hole series for cold rolling reducing of titanium and titanium alloy wire to be processed and a hole series for gauging (hole series for gauging finished products); the hole profiles of the hole series for reducing the diameter are all ten-sided hole profiles, the deformation amount of the reducing pass is 11%~17.5%, the central angle β corresponding to each face of the ten-sided hole profile is 36°, and the chamfer radius γ of the groove bottom of the ten-sided hole profile is 0.8mm~1.2mm; the chamfer R of the ten-sided hole profile is (1 / 4~1 / 3)d0, where d0 is the diameter of the circle of the cross-sectional area of ​​the ten-sided wire; the hole series for gauging the diameter adopts a circular hole profile with gradually increasing precision and gradually decreasing deformation amount, the expansion angle of the circular hole profile is 15°~25°, and the deformation amount of the gauging pass is 2%~8%.

[0020] Step 2, roll production: using an optical curve grinder to respectively produce a series of hole profiles for reducing and a series of hole profiles for calibrating on different rolls, thereby obtaining a series of rolls with hole profiles for reducing and a series of rolls with hole profiles for calibrating; the rolls are made of cold-working die steel such as Cr12MoV, SKD11, DC53, and have an HRC hardness of ≥63; the optical path system magnification of the optical curve grinder is 50 times, and the material of the grinding wheel during roll grinding is selected from white corundum, brown corundum, or diamond to ensure that the deviation between the grinding reference and the center line of the hole profile is less than 0.001 mm, and the grinding accuracy is less than 0.003 mm.

[0021] Step 3, cold rolling: first, the groove series rollers for reducing the diameter and the groove series rollers for gauging the round are respectively installed on the cold rolling mill, and a horizontal-vertical arrangement is adopted. Then, the titanium and titanium alloy wire to be processed are sequentially cold rolled using the groove series rollers for reducing the diameter and the groove series rollers for gauging the round. According to the different cold working properties of titanium and titanium alloys, some materials also need to match vacuum annealing or atmosphere protection online annealing. During the cold rolling process, the groove series rollers for reducing the diameter and the groove series rollers for gauging the round are immersed in rolling oil. The cold rolling speed is 10m / min~100m / min, and the desired titanium and titanium alloy wires are finally obtained.

[0022] In order to prove the effect of the present invention, the following examples are provided for verification. Example 1

[0023] This embodiment provides a method for cold continuous rolling of titanium and titanium alloy wires, see Figure 1-3 As shown, pure titanium-Φ5.0mm wire is prepared, and the specific steps are as follows:

[0024] Step 1: Pass Design: A series of pass types for cold tandem rolling of pure titanium are designed, all of which are 17.5% reduction passes. The central angle β corresponding to each face of the 17.5% pass is 36°, the groove bottom chamfer radius γ is 0.8mm-1.2mm, and the pass fill is 92%. The pass height H depends on the deformation per pass, the mill roll gap, and material springback. The chamfer R is (1 / 4-1 / 3)d0, where d0 is the diameter of the circle representing the cross-sectional area of ​​the 17.5% wire. After rolling, the area reduction rate for each cold tandem rolling mill stand is 17.5%. The series of pass types for rounding is a circular pass type that gradually improves the roundness and dimensional deviation accuracy, with gradually increasing accuracy and decreasing deformation. The expansion angle of the circular pass is 25°, and the rounding is designed to be three passes, with pass deformations of 8.0%, 6.5%, and 4.0%, respectively.

[0025] Step 2, roll production: After designing the pass profile, an optical curve grinder is used to respectively produce a series of pass profiles for reducing and a series of pass profiles for calibrating on different rolls to obtain a series of rolls for reducing and calibrating for cold continuous rolling of pure titanium wire; the rolls are made of Cr12MoV cold working die steel with an HRC hardness of ≥63; the optical path system magnification of the optical curve grinder is 50 times, and a white corundum grinding wheel is used during grinding to ensure that the deviation between the grinding reference and the center line of the pass profile is less than 0.001 mm, and the grinding accuracy is less than 0.003 mm.

[0026] Step 3, cold rolling: first, the groove series rollers for reducing the diameter and the groove series rollers for gauging the circle are respectively installed on 8 cold rolling mills, and arranged in a horizontal-vertical manner, and then the Φ8.9mm pure titanium wire is first rolled with the groove series rollers for reducing the diameter and then with the groove series rollers for gauging the circle for cold rolling. During the cold rolling process, the groove series rollers for reducing the diameter and the groove series rollers for gauging the circle are immersed in rolling oil, and the cold rolling speed is 50m / min~100m / min; after rolling by each cold rolling mill, the circles with equal areas of the cross section of the pure titanium wire are Φ8.08mm, Φ7.34mm, Φ6.67mm, Φ6.06mm, Φ5.50mm, Φ5.28mm, Φ5.10mm, and Φ5.0mm, respectively, and finally a Φ5.0mm pure titanium wire is prepared. Example 2

[0027] This embodiment provides a method for cold continuous rolling of titanium and titanium alloy wires, see Figure 1-3 As shown, TB14-Φ4.0mm wire is prepared. The specific steps are as follows:

[0028] Step 1: Pass Design: A series of decagonal pass types for cold tandem rolling of TB14 titanium alloy are designed. Each decagonal pass has a deformation of 13.5%. The central angle β corresponding to each face of the decagonal pass is 36°, the groove bottom chamfer radius γ is 0.8mm-1.2mm, and the pass fill is 94%. The pass height H depends on the deformation per pass, the mill roll gap, and material springback. The chamfer R is (1 / 4-1 / 3)d0, where d0 is the diameter of the circle representing the cross-sectional area of ​​the decagonal wire. After rolling, the area reduction rate for each cold tandem mill stand is 13.5%. The series of calibrating pass types is a circular pass type that gradually improves the roundness and dimensional deviation accuracy, with gradually increasing accuracy and decreasing deformation. The expansion angle of the circular pass is 20°, and the calibrating pass is designed to be three passes, with deformations of 7.0%, 5.5%, and 2.0%, respectively.

[0029] Step 2, roll production: After designing the pass profile, an optical curve grinder is used to respectively produce a series of pass profiles for reducing and a series of pass profiles for calibrating on different rolls to obtain a series of rolls for reducing and calibrating for cold rolling TB14 titanium alloy wire; the rolls are made of SKD11 cold working die steel with an HRC hardness of ≥63; the optical path system magnification of the optical curve grinder is 50 times, and a brown corundum grinding wheel is used during grinding to ensure that the deviation between the grinding reference and the center line of the pass profile is less than 0.001 mm, and the grinding accuracy is less than 0.003 mm.

[0030] Step 3, cold rolling: first, the groove series rollers for reducing the diameter and the groove series rollers for calibrating the round are installed on 13 cold rolling mills respectively, and arranged in a horizontal-vertical manner, and then the Φ8.9mmTB14 titanium alloy wire is firstly cold rolled using the groove series rollers for reducing the diameter and then using the groove series rollers for calibrating the round. During the cold rolling process, the groove series rollers for reducing the diameter and the groove series rollers for calibrating the round are immersed in rolling oil, and the cold rolling speed is 40-80m / min; each After rolling on the cold rolling mill, the circles with equal cross-sectional areas corresponding to the TB14 titanium alloy wire are Φ8.28mm, Φ7.70mm, Φ7.16mm, Φ6.66mm, Φ6.19mm, Φ5.76mm, Φ5.36mm, Φ4.98mm, Φ4.63mm, Φ4.31mm, Φ4.16mm, Φ4.04mm, and Φ4.0mm, respectively, and finally TB14 titanium alloy wire with a diameter of Φ4.0mm is prepared. Example 3

[0031] This embodiment provides a method for cold continuous rolling of titanium and titanium alloy wires, see Figure 1-3 As shown, TC16-Φ3.0mm wire is prepared. The specific steps are as follows:

[0032] Step 1. Pass Design: A series of 10-sided pass types for cold tandem rolling of TC16 titanium alloy are designed. Each reduction pass has an 11% deformation. The central angle β corresponding to each face of the 10-sided pass is 36°, the groove bottom chamfer radius γ is 0.8mm-1.2mm, and the pass fill is 94%. The pass height H depends on the deformation per pass, the mill roll gap, and the material springback. The chamfer R is (1 / 4-1 / 3)d0, where d0 is the diameter of the circle representing the cross-sectional area of ​​the 10-sided wire. After rolling, the area reduction rate for each cold tandem rolling mill stand is 11%. The series of rounding pass types is a circular pass type that gradually improves the roundness and dimensional deviation accuracy, with gradually increasing accuracy and decreasing deformation. The expansion angle of the circular pass is 15°, and the rounding is designed to be three passes, with deformations of 8.0%, 7.0%, and 3.5%, respectively.

[0033] Step 2, roll production: After designing the pass profile, an optical curve grinder is used to respectively produce a series of pass profiles for reducing and a series of pass profiles for calibrating on different rolls to obtain a series of rolls for reducing and calibrating for cold rolling TC16 titanium alloy wire; the rolls are made of DC53 cold working die steel with an HRC hardness of ≥63; the optical path system magnification of the optical curve grinder is 50 times, and a diamond grinding wheel is used during grinding to ensure that the deviation between the grinding reference and the center line of the pass profile is less than 0.001 mm, and the grinding accuracy is less than 0.003 mm.

[0034] Step 3, cold rolling and intermediate annealing: first, the groove series rollers for reducing the diameter and the groove series rollers for gauging the circle are installed on 20 cold rolling mills respectively, and arranged in a horizontal-vertical manner, and then the Φ8.9mmTC16 titanium alloy wire is first cold rolled using the groove series rollers for reducing the diameter and then using the groove series rollers for gauging the circle. During the cold rolling process, the groove series rollers for reducing the diameter and the groove series rollers for gauging the circle are immersed in rolling oil, and the cold rolling speed is 10m / min~50m / min; after rolling by each cold rolling mill, the circles with equal cross-sectional areas corresponding to the TC16 titanium alloy wire are Φ8.40mm, Φ7.92mm, Φ7.47mm, Φ7.05mm, Φ6.9mm, etc., respectively. .65mm, Φ6.27mm, Φ5.92mm, Φ5.58mm, Φ5.27mm, Φ4.97mm, Φ4.69mm, Φ4.42mm, Φ4.17mm, Φ3.94mm, Φ3.71mm, Φ3.50mm, Φ3.31mm, Φ3.17mm, Φ3.06mm, Φ3.0mm. According to the cold working properties of TC16 titanium alloy, when the cumulative deformation is between 55% and 70% for the first time after cold rolling, intermediate vacuum annealing or argon protection annealing is required, and the annealing temperature is 650℃~750℃. After cooling, cold rolling is continued to finally prepare TC16 titanium alloy wire with a diameter of Φ3.0mm.

[0035] To further verify the effectiveness of the technical solution provided by the present invention, a digital micrometer was used to measure the dimensions of the head, 1 / 4, middle, 3 / 4, and tail of the 50kg~100kg grade pure titanium wire, TB14 titanium alloy wire, and TC16 titanium alloy wire prepared in the above embodiment. The maximum and minimum points of each part were measured multiple times. The results are shown in Table 1:

[0036] Table 1

[0037]

[0038] In summary, it can be seen from Table 1 that the titanium and titanium alloy wires prepared under high-speed rolling conditions by using the cold rolling groove series for reducing diameter and the groove series for squaring diameter of the present invention can ensure that their out-of-roundness is within 0.02 mm, which can meet the high-efficiency and high-precision forming requirements of titanium and titanium alloy wires.

[0039] It should also be noted that the cross-sectional area of ​​the wire can be calculated using the groove width, hole height H, hole fill degree, and area reduction rate.

[0040] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0041] It should be understood that the present invention is not limited to the above description and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for cold continuous rolling of titanium alloy wire, characterized in that: Preparation of TC16-Φ3.0mm wire includes the following steps: Step 1, pass design: Design a series of pass types for cold rolling reduction of TC16 titanium alloy and a series of pass types for gauging. The pass types for reducing are all decagonal pass types, and the deformation of the reducing pass is 11%. The central angle β corresponding to each face of the decagonal pass is 36°, the groove bottom chamfer radius γ is 0.8mm~1.2mm, the pass fill is 94%, and the chamfer R is (1 / 4~1 / 3)d0, where d0 is the diameter of the circle of the cross-sectional area of ​​the decagonal wire. After rolling, the area reduction rate of each cold rolling mill stand is 11%, the series of pass types for gauging are all circular pass types, the expansion angle of the circular pass is 15°, the gauging is designed for 3 passes, and the deformation of the passes are 8.0%, 7.0%, and 3.5%, respectively. Step 2, roll production: the diameter-reducing pass series and the rounding pass series are produced on different rolls respectively, to obtain the diameter-reducing pass series rolls and the rounding pass series rolls for cold continuous rolling of TC16 titanium alloy wire; Step 3, cold rolling and intermediate annealing: First, the grooved series rollers for reducing and the grooved series rollers for squaring are installed on 20 cold rolling mills in a horizontal-vertical arrangement. Then, Φ8.9 mm TC16 titanium alloy wire is cold rolled first using the grooved series rollers for reducing and then using the grooved series rollers for squaring at a speed of 10 m / min to 50 m / min. After rolling on each cold rolling mill, the circles with equal cross-sectional areas corresponding to the TC16 titanium alloy wire are Φ8.40 mm, Φ7.92 mm, Φ7.47 mm, Φ7.05 mm, Φ6.65 mm, Φ6.27 mm, and Φ5. 92mm, Φ5.58mm, Φ5.27mm, Φ4.97mm, Φ4.69mm, Φ4.42mm, Φ4.17mm, Φ3.94mm, Φ3.71mm, Φ3.50mm, Φ3.31mm, Φ3.17mm, Φ3.06mm, Φ3.0mm. According to the cold working properties of TC16 titanium alloy, when the cumulative deformation is between 55% and 70% for the first time after cold rolling, intermediate vacuum annealing or argon protection annealing is required. The annealing temperature is 650℃~750℃. After cooling, cold rolling is continued to finally prepare Φ3.0mm TC16 titanium alloy wire.

2. The rolling method according to claim 1, characterized in that In step 2, the material of the rolling roller is one of Cr12MoV, SKD11, and DC53, and the HRC hardness is ≥63.

3. The rolling method according to claim 1, characterized in that In step 2, an optical curve grinder is used to respectively produce a series of rollers with a hole shape for reducing diameter and a series of rollers with a hole shape for squaring roundness. The optical curve grinder has an optical path system magnification of 50 times and a grinding accuracy of less than 0.003 mm.

4. The rolling method according to claim 1, characterized in that In step 3, the groove series rolls for reducing diameter and the groove series rolls for calibrating roundness are immersed in rolling oil during the cold rolling process.

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