A method for manufacturing a titanium alloy profiled ring

Abstract

The application relates to a titanium alloy special-shaped ring piece preparation technical field, in particular to a titanium alloy special-shaped ring piece preparation method, which comprises the following steps: step one, blank preparation; step two, blank machining, adopting a skinning machine to remove surface oxide scales, obtaining a titanium alloy round bar blank with a diameter of 220 mm, and carrying out sawing treatment, and machining positioning holes at the center position of one end of the bar blank; step three, inclined rolling piercing, after heating and heat preservation in an electric furnace, the bar blank with the positioning holes is pierced into an inclined rolling machine, step feeding is carried out, and the bar blank is subjected to open die rolling piercing to form a pipe blank with a diameter of 240 / 120*L; step four, hot continuous rolling, heating and heat preservation are carried out in the electric furnace, and three-step step-by-step rotary three-roller rolling is carried out; step five, finishing machining, the pipe blank is cut, the blank is cut into a ring blank, the inner and outer surfaces are coarsely turned, the ring piece is subjected to quality inspection, and semi-finishing machining is carried out; after cleaning, drying and vacuum stress relief annealing, the ring piece is slowly cooled in the furnace under vacuum, finally, the finished ring is subjected to finishing machining, appearance size inspection, code spraying and packaging.

Description

Technical Field

[0001] This invention relates to the field of titanium alloy irregular-shaped ring manufacturing technology, specifically a method for manufacturing titanium alloy irregular-shaped rings. Background Technology

[0002] Titanium alloy rings are generally formed by punching and rolling a bar blank into a ring. This traditional process is relatively simple, but it is difficult to control the surface and roundness of the rolled ring blank to an ideal degree, and the subsequent machining allowance is too large, resulting in high processing costs.

[0003] Extrusion tubes are difficult to use in industrial applications because of the high extrusion pressure and the high deformation resistance of titanium alloys. However, extruding thin-walled tubes can easily cause surface cracking and uneven thickness.

[0004] Titanium alloy tubes can be produced using a single skew rolling piercing method to obtain small-diameter tubes, but the rolling is carried out in a high-temperature zone, causing the material microstructure to overheat and failing to meet the processing microstructure requirements of the two-phase region, thus limiting its application. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing titanium alloy irregular ring parts, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for preparing a titanium alloy irregular ring includes the following steps:

[0008] Step 1: Billet preparation. Select a Φ230mm titanium alloy round bar billet that has been forged and precision-forged through multiple upsetting and drawing processes.

[0009] Step 2, billet machining: Take the titanium alloy round bar billet obtained in Step 1, remove the surface oxide scale using a peeling machine to obtain a Φ220mm titanium alloy round bar billet, and perform sawing. Machining a positioning hole at the center of one end of the billet.

[0010] Step 3, skew rolling and piercing: Take the titanium alloy billet obtained in step 2, heat and hold it in an electric furnace, then insert the end of the billet with the positioning hole into the skew rolling mill, feed it in step, and perform billet rolling and piercing to Φ240 / Φ120*L.

[0011] Step 4, hot continuous rolling: Take the rolled Φ240 / Φ120*L billet obtained in step 3, place it in an electric furnace for heating and holding, and perform three-stage stepping rotary three-roll rolling to obtain titanium alloy continuously rolled tube billet.

[0012] Step 5, finishing machining: Take the titanium alloy continuous rolling tube billet obtained in step 4, cut the tube billet into a ring billet, rough machine the inner and outer surfaces to obtain a rough machined ring, inspect the ring, and then perform semi-finishing. After cleaning, drying, vacuum stress-relief annealing, slow cooling in the furnace under vacuum, the finished ring is finally finished, with appearance and size inspection, coding, and packaging.

[0013] As a further aspect of the present invention, the steps of the three-stage stepping rotary three-roll rolling are as follows:

[0014] The first stage involves continuous rolling of the tube at 960℃ in 6 passes.

[0015] The second stage involves continuous rolling of the tube at 930℃ in 6 passes, which expands the hole, reduces the wall thickness, and decreases the outer diameter.

[0016] The third stage involves sizing the inner and outer diameters at 900℃ in four passes to control the finished product dimensions. After rolling, the product is straightened online at 800℃ for 40 minutes using a multi-roll skew straightening process to obtain a titanium alloy continuously rolled tube blank.

[0017] As a further aspect of the present invention: in step two, after removing the oxide scale from the titanium alloy round bar blank, the sawing length is 500mm.

[0018] As a further aspect of the present invention: in step two, the size of the positioning hole at the end of the billet is Φ50*30mm.

[0019] As a further aspect of the present invention: in step three, the heating and heat preservation temperature in the electric furnace is 1040°C.

[0020] As a further aspect of the present invention: in step five, a finishing allowance of 0.2-0.3 mm is reserved for semi-finishing.

[0021] As a further aspect of the present invention: in step five, the annealing environment is 620°C and maintained for 2 hours.

[0022] As a further aspect of the present invention, the quality inspection in step five includes ultrasonic flaw detection, high and low magnification, and tensile property testing.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] (1) This invention creatively draws on the continuous bar rolling technology, using a rolling center mandrel for positioning and rotating three rolls to achieve continuous multi-stage, multi-pass hot rolling with a step-by-step spiral advance. This enables large deformation rolling of the billet for thermoplastic deformation, fully breaking down and refining the phase structure of the titanium alloy, and effectively controlling the rolling roundness and wall thickness uniformity. It also breaks through the technical problem that two-phase titanium alloy billets cannot be rolled below the phase transformation point.

[0025] (2) In the temperature range below the phase transformation point of titanium alloy, the desired large-size thin-walled tube material is obtained by multi-stage temperature drop segmented heating and step-by-step spiral three-roll rolling. The material microstructure and properties meet the technical standard requirements.

[0026] (3) The rough-machined ring is obtained by machining the tube, and then semi-finished, vacuum stress-relief annealing and finishing are carried out to effectively avoid the deformation problem caused by residual stress on the machining surface of the thin-walled irregular structure, thus producing a titanium alloy irregular ring with high dimensional accuracy.

[0027] (4) The use of one-time hot continuous rolling to form pipe greatly improves the processing and preparation efficiency, reduces the hot processing cost, and has high precision in controlling the size and surface of the rolled pipe blank. The subsequent machining allowance is small, which greatly reduces the machining loss of ring parts and reduces the manufacturing cost of special-shaped ring parts. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the manufacturing process for titanium alloy irregular ring parts.

[0029] Figure 2 This is a schematic diagram of a rotating three-roll tube rolling mechanism in one embodiment of a method for preparing titanium alloy irregular ring parts.

[0030] Figure 3 for Figure 2 A cross-sectional view along the aa direction.

[0031] Figure 4 This is a schematic diagram of the structure of a titanium alloy irregular ring component in one embodiment of a method for preparing a titanium alloy irregular ring component.

[0032] Figure 5 This is a schematic diagram of the microstructure of the cross-section of the ring component. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Furthermore, elements in this invention are referred to as being "fixed to" or "set on" another element, which may be directly on the other element or may also include an intervening element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or may also include an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations.

[0035] Please see Figures 1-5 In this embodiment of the invention, a method for preparing a titanium alloy irregular ring includes the following steps:

[0036] Step 1: Billet preparation. Select a Φ230mm titanium alloy round bar billet that has been forged and precision-forged through multiple upsetting and drawing processes.

[0037] Step 2, billet machining: Take the titanium alloy round bar billet obtained in Step 1, remove the surface oxide scale using a peeling machine to obtain a Φ220mm titanium alloy round bar billet, and perform sawing. Machining a positioning hole at the center of one end of the billet.

[0038] Step 3, skew rolling and piercing: Take the titanium alloy billet obtained in step 2, heat and hold it in an electric furnace, then insert the end of the billet with the positioning hole into the skew rolling mill, feed it in step, and perform billet rolling and piercing to Φ240 / Φ120*L.

[0039] Step 4, hot continuous rolling: Take the rolled Φ240 / Φ120*L billet obtained in step 3, place it in an electric furnace for heating and holding, and perform three-stage stepping rotary three-roll rolling to obtain titanium alloy continuously rolled tube billet.

[0040] Step 5, finishing machining: Take the titanium alloy continuous rolling tube billet obtained in step 4, cut the tube billet into a ring billet, rough machine the inner and outer surfaces to obtain a rough machined ring, inspect the ring, and then perform semi-finishing. After cleaning, drying, vacuum stress-relief annealing, slow cooling in the furnace under vacuum, the finished ring is finally finished, with appearance and size inspection, coding, and packaging.

[0041] The steps of the three-stage stepping rotary three-roll rolling process are as follows:

[0042] The first stage involves continuous rolling of the tube at 960℃ in 6 passes.

[0043] The second stage involves continuous rolling of the tube at 930℃ in 6 passes, which expands the hole, reduces the wall thickness, and decreases the outer diameter.

[0044] The third stage involves sizing the inner and outer diameters at 900℃ in four passes to control the finished product dimensions. After rolling, the product is straightened online at 800℃ for 40 minutes using a multi-roll skew straightening process to obtain a titanium alloy continuously rolled tube blank.

[0045] In step two, after removing the oxide scale from the titanium alloy round bar billet, the sawing length is 500mm.

[0046] In step two, the size of the positioning hole at the end of the billet is Φ50*30mm.

[0047] In step three, the heating and heat preservation temperature in the electric furnace is 1040℃.

[0048] In step five, a finishing allowance of 0.2-0.3 mm is reserved for semi-finishing.

[0049] In step five, the annealing environment is 620℃ and maintained for 2 hours.

[0050] The quality inspection in step five includes ultrasonic flaw detection, high and low magnification testing, and tensile property testing.

[0051] As an example, the microstructure of the cross-section of the ring was observed, and the results are attached. Figure 5 As shown.

[0052] In addition, the transverse room temperature mechanical properties of the ring were tested, and the test results are shown in Table 1:

[0053] Table 1

[0054]

[0055] Based on the above data, the innovative points and beneficial effects of this invention can be inferred as follows:

[0056] (1) This invention creatively draws on the continuous bar rolling technology, using a rolling center mandrel for positioning and rotating three rolls to achieve continuous multi-stage, multi-pass hot rolling with a step-by-step spiral advance. This enables large deformation rolling of the billet for thermoplastic deformation, fully breaking down and refining the phase structure of the titanium alloy, and effectively controlling the rolling roundness and wall thickness uniformity. It also breaks through the technical problem that two-phase titanium alloy billets cannot be rolled below the phase transformation point.

[0057] (2) In the temperature range below the phase transformation point of titanium alloy, the desired large-size thin-walled tube material is obtained by multi-stage temperature drop segmented heating and step-by-step spiral three-roll rolling. The material microstructure and properties meet the technical standard requirements.

[0058] (3) The rough-machined ring is obtained by machining the tube, and then semi-finished, vacuum stress-relief annealing and finishing are carried out to effectively avoid the deformation problem caused by residual stress on the machining surface of the thin-walled irregular structure, thus producing a titanium alloy irregular ring with high dimensional accuracy.

[0059] (4) The use of one-time hot continuous rolling to form tubes greatly improves the processing and preparation efficiency and reduces the hot processing cost; the size and surface control accuracy of the rolled tube blank is high, and the subsequent machining allowance is small, which greatly reduces the machining loss of ring parts and reduces the manufacturing cost of special-shaped ring parts.

[0060] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0061] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a titanium alloy irregular ring, characterized in that, Includes the following steps: Step 1: Billet preparation. Select a Φ230mm titanium alloy round bar billet that has been forged and precision-forged through multiple upsetting and drawing processes. Step 2, billet machining: Take the titanium alloy round bar billet obtained in Step 1, remove the surface oxide scale using a peeling machine to obtain a Φ220mm titanium alloy round bar billet, and then perform sawing. Machining a positioning hole at the center of one end of the billet. Step 3, skew rolling and piercing: Take the titanium alloy billet obtained in step 2, heat and hold it in an electric furnace, then insert the end of the billet with the positioning hole into the skew rolling mill, feed it in step, and perform billet rolling and piercing to Φ240 / Φ120*L. Step 4, hot continuous rolling: Take the rolled Φ240 / Φ120*L billet obtained in Step 3, place it in an electric furnace for heating and holding, and perform three-stage walking rotary three-roll rolling to obtain a titanium alloy continuously rolled tube billet; the three-stage walking rotary three-roll rolling process is as follows: First stage, using 960℃, 6 passes of tube continuous rolling; Second stage, using 930℃, 6 passes of tube continuous rolling, expanding the hole, thinning the wall thickness, and reducing the outer diameter; Third stage, using 900℃, 4 passes of inner and outer diameter sizing rolling to control the finished product size; After rolling, at 800℃ for 40 minutes, online multi-roll skew straightening is performed to obtain a titanium alloy continuously rolled tube billet; Step 5, finishing machining: Take the titanium alloy continuously rolled tube billet obtained in step 4, cut the tube billet into a ring billet, rough machine the inner and outer surfaces to obtain a rough machined ring, inspect the ring, and then perform semi-finishing. After cleaning, drying, vacuum stress-relief annealing, slow cooling in the furnace under vacuum, the finished ring is finally finished, and the appearance and dimensions are inspected, marked, and packaged.

2. The method for preparing a titanium alloy irregular ring according to claim 1, characterized in that, In step two, after removing the oxide scale from the titanium alloy round bar billet, the sawing length is 500mm.

3. The method for preparing a titanium alloy irregular ring according to claim 1, characterized in that, In step two, the size of the positioning hole at the end of the billet is Φ50*30mm.

4. The method for preparing a titanium alloy irregular ring according to claim 1, characterized in that, In step three, the heating and heat preservation temperature in the electric furnace is 1040℃.

5. The method for preparing a titanium alloy irregular ring according to claim 1, characterized in that, In step five, a finishing allowance of 0.2-0.3 mm is reserved for semi-finishing.

6. The method for preparing a titanium alloy irregular ring according to claim 1, characterized in that, In step five, the annealing environment is 620℃ and maintained for 2 hours.

7. The method for preparing a titanium alloy irregular ring according to claim 1, characterized in that, The quality inspection in step five includes ultrasonic flaw detection, high and low magnification testing, and tensile property testing.

Images