Preparation method of high-toughness corrosion-resistant titanium alloy pipe

Abstract

The application discloses a preparation method of high-strength and high-toughness corrosion-resistant titanium alloy pipe, and relates to the field of titanium alloy pipe preparation methods.The method comprises the following steps: firstly, titanium alloy ingots are subjected to multi-fire forging deformation and one-time precision forging deformation in sequence to obtain titanium alloy bars; secondly, the titanium alloy bars are mechanically processed into extrusion blanks and subjected to jacket extrusion to obtain extruded pipe blanks; and thirdly, the extruded pipe blanks are subjected to heat treatment to obtain high-strength and high-toughness corrosion-resistant titanium alloy pipes.The titanium alloy ingots are prepared into bars by high-efficiency fine-grain forging and precision forging methods, then the titanium alloy extrusion blanks are processed, the pipe blanks are prepared by extrusion, and finally the titanium alloy pipes are obtained by heat treatment, so that the titanium alloy pipes have excellent organization and performance, meet the high-strength and high-toughness corrosion-resistant requirements of oil and gas exploration and exploitation service environments, and the process flow is simple and the cost is low.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of titanium alloy, and particularly relates to a preparation method of high-strength and high-toughness corrosion-resistant titanium alloy pipe. BACKGROUND

[0002] Titanium and titanium alloy are widely concerned in the fields of marine engineering and petroleum chemical industry due to their excellent specific strength and corrosion resistance, and the demand for high-strength, high-toughness and high-corrosion-resistant titanium alloy pipe for marine engineering increases year by year. The high-strength and high-toughness corrosion-resistant titanium alloy in China is still in the research and trial production stage, and the related pipe preparation technology is not mature, which cannot be stably applied in engineering.

[0003] At present, there are many preparation methods for high-strength and high-toughness titanium alloy pipe and excellent performance is obtained, but there are still limitations, and no related data of pipe corrosion resistance are seen. The patent with publication number CN109706344A discloses a titanium alloy pipe with a yield strength of 935 MPa, a tensile strength of 1005 MPa, a transverse elongation of 15%, and a full-size Charpy V-type impact energy of 49 J. The patent with publication number CN111593230A discloses a titanium alloy pipe with a yield strength R 0.2 ≥933 MPa, a tensile strength Rm≥1051 MPa, an elongation δ≥10%, and an impact energy AKV≥60 J. The pipes prepared by these process methods all have good mechanical properties, but their service environments are mostly high-strength and high-toughness environments that require bearing capacity. For titanium alloy pipes used in complex oil exploration and production service conditions, the material not only needs to have higher strength and excellent impact resistance, but also needs to have corrosion resistance in harsh environments.

[0004] The patent with publication number CN117802351A discloses a high-strength and corrosion-resistant titanium alloy pipe and a preparation method thereof, but does not describe the impact toughness of the material. As known, the high-strength titanium alloy pipe is affected by temperature and stress during the forming process, and it is very difficult to control the formability and microstructure. The addition of corrosion-resistant alloy elements will further reduce the formability of the pipe. The existing process is difficult to balance the control of pipe shape and microstructure of difficult-to-deform titanium alloy. It is difficult for domestic titanium enterprises to coordinate the pipe preparation process parameters and microstructure to prepare high-strength and high-toughness corrosion-resistant titanium alloy pipe. The preparation of high-strength and high-toughness corrosion-resistant titanium alloy pipe in China is still in the exploratory stage, and no reliable technology has been formed.

[0005] The patent with the publication number CN107541615A discloses a titanium alloy for ocean engineering, which has good corrosion resistance and welding performance. The alloy has more beneficial strength and toughness than traditional ship titanium alloy, and has excellent corrosion resistance, and has great application prospect. However, due to the addition of corrosion-resistant elements such as Zr and Mo, the material has large deformation resistance in the two-phase region and is difficult to form. Therefore, it is of great significance to explore the preparation method of the new high-strength and toughness corrosion-resistant titanium alloy pipe for improving the preparation technology of high-performance titanium alloy pipe for ocean engineering in China and expanding the application of titanium alloy pipe. SUMMARY

[0006] The technical problem to be solved by the present application is to provide a preparation method of high-strength and toughness corrosion-resistant titanium alloy pipe to solve the problem of lack of reliable high-strength and toughness corrosion-resistant titanium alloy pipe preparation process in the prior art.

[0007] To solve the above technical problems, the technical scheme adopted by the present application is as follows: a preparation method of high-strength and toughness corrosion-resistant titanium alloy pipe, characterized in that the method comprises the following steps:

[0008] Step one, titanium alloy ingot is sequentially subjected to multi-fire forging deformation and one-time precision forging deformation to obtain titanium alloy bar blank; the titanium alloy ingot is composed of the following components by mass percentage: Al 6.0% to 6.7%, Sn 0.5% to 2.0%, Zr 3.5% to 4.5%, Mo 1% to 1.15%, V 0.5% to 1.5%, Nb 2.0% to 3.1%, and the balance is Ti and unavoidable impurities;

[0009] Step two, the titanium alloy bar blank obtained in step one is mechanically processed into an extrusion blank and subjected to jacket extrusion to obtain an extruded pipe blank;

[0010] Step three, the extruded pipe blank obtained in step two is subjected to heat treatment to obtain a high-strength and toughness corrosion-resistant titanium alloy pipe; the yield strength of the titanium alloy pipe is not less than 900 MPa, the elongation is not less than 10%, the impact energy at-20℃ is not less than 50 J, and the high-strength corrosion-resistant titanium alloy pipe does not break after 720 hours of testing according to the NACE TM0177-2016 test standard in test solution A under a stress corresponding to 76% nominal yield strength.

[0011] The above-mentioned method for preparing a high-strength, toughness, and corrosion-resistant titanium alloy pipe is characterized in that the multi-fire forging deformation process described in step one is: heating the titanium alloy ingot to 50°C to 90°C above the β phase transformation point temperature and performing two-fire three-time reversing upsetting forging, with a single deformation amount of 30% to 40%; then heating the deformed forging to 10°C to 20°C above the β phase transformation point temperature and performing two-fire three-time reversing upsetting forging, with a single deformation amount of 30%, and water cooling after forging; then heating the deformed forging to 10°C to 20°C below the β phase transformation point temperature and performing one-fire conventional forging, with a single deformation amount of 30%, and water cooling after forging.

[0012] The above-mentioned method for preparing a high-strength, toughness, and corrosion-resistant titanium alloy pipe is characterized in that the process of the single fine forging deformation in step one is: heating the titanium alloy forging obtained by multiple forging deformations to a temperature 10°C to 20°C below the β phase transformation point and then performing fine forging deformation, and the deformation amount of the fine forging deformation is not less than 40%.

[0013] The above-mentioned method for preparing a high-strength, toughness, and corrosion-resistant titanium alloy pipe is characterized in that the process of mechanically processing the rod blank into an extruded blank in step 2 is: the rod blank is machined into an extruded blank with an outer diameter of φ181mm and an inner diameter of φ79mm, and the outer diameter tolerance is -1mm to 0mm, and one end of the extruded blank is chamfered R10 to 15.

[0014] The above-mentioned method for preparing a high-strength, toughness, and corrosion-resistant titanium alloy pipe is characterized in that the sheath extrusion process in step 2 is:

[0015] Step 201: Coat the extruded blank with asbestos and copper to obtain a coated extruded blank;

[0016] Step 202: heating the jacketed extrusion blank obtained in step 201 in an induction heating furnace and keeping the temperature for 60 minutes; the heating temperature is 10° C. below the β phase transition point temperature to 40° C. above the β phase transition point temperature;

[0017] Step 203: Place the heated and insulated sheathed extruded billet in step 202 on an extruder for extrusion. The extrusion barrel size used is φ185 mm in inner diameter, the preheating temperature is 200°C, and a high-temperature lubricant is applied. The extrusion ratio is controlled to be 7.3 to 10.1, and the extrusion speed is 35 mm / s to 40 mm / s.

[0018] The above-mentioned method for preparing a high-strength, toughness, and corrosion-resistant titanium alloy pipe is characterized in that the heat treatment in step three includes solution heat treatment and aging heat treatment, wherein the solution heat treatment system is: keeping warm at 50°C to 80°C below the β phase transformation point for 1h to 2h, and air cooling, and the aging heat treatment system is: keeping warm at 550°C to 600°C for 4h, and air cooling.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] 1、The present application firstly provides the basic performance of the titanium alloy material through the accurate control of the titanium alloy composition, then prepares the bar blank through multi-fire forging deformation and one-time precision forging deformation, effectively refines the material organization grain, provides guarantee for the subsequent extrusion deformation, and through the precision forging deformation of the forged piece after sufficient deformation, forms the gradient fine grain layer on the surface, which is beneficial to improve the surface deformation quality of the extruded blank after the subsequent extrusion deformation, reduces the contact temperature drop loss in the extrusion process through the cladding extrusion, and finally obtains the titanium alloy pipe through heat treatment, which effectively guarantees that the titanium alloy pipe has excellent organization and performance, meets the high strength and toughness and corrosion resistance requirements of the oil and gas exploration and exploitation service environment, and has simple process flow and low cost.

[0021] 2、The present application effectively and uniformly refines the grain size of the forged piece through the control of the deformation mode, deformation amount and deformation temperature of the multi-fire forging deformation, retains the fine grain structure through the water cooling means after forging, and provides the organization basis for the subsequent forging.

[0022] 3、The present application controls the temperature and deformation amount of one-time precision forging deformation, on the one hand to ensure that the optimal organization structure is obtained, and on the other hand to obtain the surface fine grain layer, improve the surface organization deformation coordination in the extrusion process, reduce the surface cracking, and improve the surface quality.

[0023] 4、The present application adopts the composite cladding means and the accurate cooperation of the extrusion size, combines the control of the extrusion temperature, the extrusion cylinder, the extrusion process parameters and the heat treatment parameters, effectively reduces the extrusion temperature drop, and guarantees that the titanium alloy pipe with excellent performance is obtained.

[0024] The technical solutions of the present application will be further described in detail through the following examples. DETAILED DESCRIPTION

[0025] Example 1

[0026] The present embodiment includes the following steps:

[0027] Step one, titanium alloy ingot is subjected to multi-fire forging deformation and one-time precision forging deformation in sequence to obtain titanium alloy bar blank; the titanium alloy ingot is composed of the following components in mass percentage: Al 6.0%, Sn 1.02%, Zr 3.59%, Mo 1.09%, V 1.0%, Nb 2.88%, and the balance is Ti and inevitable impurities;

[0028] The process of the multi-fire forging deformation is that: the titanium alloy ingot is heated to 90 DEG C above the beta transus temperature for one fire three-way upsetting and drawing forging, the single deformation amount is 40%, then the deformed forging is heated to 50 DEG C above the beta transus temperature for one fire three-way upsetting and drawing forging, the single deformation amount is 30%; then the deformed forging is heated to 20 DEG C above the beta transus temperature for two fires three-way upsetting and drawing forging, the single deformation amount is 30%, and water cooling after forging; then the deformed forging is heated to 10 DEG C below the beta transus temperature for one fire conventional forging, the single deformation amount is 30%, and water cooling after forging;

[0029] The process of the one-time precision forging deformation is that: the titanium alloy forging obtained through the multi-fire forging deformation is heated to 10 DEG C below the beta transus temperature for precision forging deformation, and the deformation amount of the precision forging deformation is 47%;

[0030] Step two, the titanium alloy bar blank obtained in step one is machined into an extrusion blank, and a jacketed extrusion is carried out to obtain an extruded pipe blank;

[0031] The process of machining the bar blank into an extrusion blank is that: the bar blank is machined into an extrusion blank with an outer diameter of 180 mm and an inner diameter of 79 mm, and the outer diameter tolerance is-0.5 mm, and the extrusion blank is chamfered at one end with R15;

[0032] The process of the jacketed extrusion is that:

[0033] Step 201, the extrusion blank is coated with asbestos and red copper to obtain a jacketed extrusion blank;

[0034] Step 202, the jacketed extrusion blank obtained in step 201 is heated to 10 DEG C below the beta transus temperature in an induction heating furnace and is kept for 60 min;

[0035] Step 203, the jacketed extrusion blank after heating and keeping in step 202 is placed on an extrusion machine for extrusion, the extrusion cylinder size is an inner diameter of 185 mm, the preheating temperature is 200 DEG C, and high-temperature lubricant is applied, the extrusion ratio is controlled to be 7.3, and the extrusion speed is 35 mm / s;

[0036] Step three, the extruded pipe blank obtained in step two is subjected to heat treatment to obtain a high-strength and high-toughness corrosion-resistant titanium alloy pipe; the heat treatment includes solid solution heat treatment and aging heat treatment, wherein the solid solution heat treatment system is: keeping at 50 DEG C below the beta transus temperature for 2 h, and air cooling, and the aging heat treatment system is: keeping at 550 DEG C for 4 h, and air cooling.

[0037] The titanium alloy pipe prepared in the embodiment has a yield strength of 926 MPa, an elongation of 13.5%, and an impact energy at-20℃ of 53.8 J. According to the test standard NACE TM0177-2016, the high-strength corrosion-resistant titanium alloy pipe is tested in test solution A under a stress corresponding to 76% of the nominal yield strength for 720 hours, and no fracture occurs.

[0038] Example 2

[0039] The embodiment includes the following steps:

[0040] Step one, the titanium alloy ingot is subjected to multi-pass forging deformation and one-pass precision forging deformation in sequence to obtain a titanium alloy bar blank; the titanium alloy ingot is composed of the following components in mass percentage: Al 6.03%, Sn 1.02%, Zr 3.65%, Mo 1.08%, V 1.0%, Nb 2.87%, and the balance of Ti and unavoidable impurities;

[0041] The process of the multi-pass forging deformation is as follows: the titanium alloy ingot is heated to a temperature 90℃ above the beta transus temperature for one-pass three-way upset and drawing forging, and the single deformation amount is 40%; then the deformed forging is heated to a temperature 50℃ above the beta transus temperature for one-pass three-way upset and drawing forging, and the single deformation amount is 30%; then the deformed forging is heated to a temperature 20℃ above the beta transus temperature for two-pass three-way upset and drawing forging, and the single deformation amount is 30%, and the forging is water-cooled after forging; then the deformed forging is heated to a temperature 20℃ below the beta transus temperature for one-pass conventional forging, and the single deformation amount is 30%, and the forging is water-cooled after forging;

[0042] The process of the one-pass precision forging deformation is as follows: the titanium alloy forging obtained by the multi-pass forging deformation is heated to a temperature 20℃ below the beta transus temperature for precision forging deformation, and the deformation amount of the precision forging deformation is 42%;

[0043] Step two, the titanium alloy bar blank obtained in step one is machined into an extrusion blank, and is subjected to jacketed extrusion to obtain an extruded pipe blank;

[0044] The process of machining the bar blank into an extrusion blank is as follows: the bar blank is machined into an extrusion blank with an outer diameter of φ181mm and an inner diameter of φ79mm, and the outer diameter tolerance is-1mm, and the extrusion blank is chamfered at one end with a chamfer of R10;

[0045] The process of the jacketed extrusion is as follows:

[0046] Step 201, the extrusion blank is coated with asbestos and red copper in combination to obtain a jacketed extrusion blank;

[0047] Step 202, heating the cladding extrusion blank obtained in step 201 to 40℃ above the beta transus temperature in an induction heating furnace and holding for 60 min;

[0048] Step 203, placing the cladding extrusion blank after heating and holding in step 202 on an extruder to perform extrusion, the size of the extrusion cylinder used is an inner diameter of φ185 mm, the preheating temperature is 200℃, and high-temperature lubricant is applied, the extrusion ratio is controlled to be 10.1, and the extrusion speed is 40 mm / s;

[0049] Step three, performing heat treatment on the extruded pipe blank obtained in step two to obtain the high-strength and tough corrosion-resistant titanium alloy pipe; the heat treatment comprises solid solution heat treatment and aging heat treatment, wherein the solid solution heat treatment has a regime of holding for 2 h at 80℃ below the beta transus temperature and air cooling, and the aging heat treatment has a regime of holding for 4 h at 600℃ and air cooling.

[0050] It is detected that the yield strength of the titanium alloy pipe prepared in the embodiment is 906 MPa, the elongation is 11%, the impact energy at -20℃ is 58 J, and the high-strength corrosion-resistant titanium alloy pipe does not break after 720 hours of testing according to the NACE TM0177-2016 test standard in the test solution A under a stress corresponding to 76% of the nominal yield strength.

[0051] Example 3

[0052] The embodiment comprises the following steps:

[0053] Step one, sequentially performing multi-pass forging deformation and one-pass precision forging deformation on a titanium alloy ingot to obtain a titanium alloy bar blank; the titanium alloy ingot is composed of the following components in mass percentage: Al 6.7%, Sn 1.0%, Zr 4.5%, Mo 1.15%, V 1.5%, Nb 3.1%, and the balance being Ti and unavoidable impurities;

[0054] The process of the multi-pass forging deformation is as follows: heating the titanium alloy ingot to 90℃ above the beta transus temperature to perform one-pass three-way upset and drawing forging, and the single deformation amount is 40%; then heating the deformed forging to 60℃ above the beta transus temperature to perform one-pass three-way upset and drawing forging, and the single deformation amount is 30%; then heating the deformed forging to 10℃ above the beta transus temperature to perform two-pass three-way upset and drawing forging, and the single deformation amount is 30%, and water cooling after forging; then heating the deformed forging to 10℃ below the beta transus temperature to perform one-pass conventional forging, and the single deformation amount is 30%, and water cooling after forging;

[0055] The process of the one-pass precision forging deformation is as follows: heating the titanium alloy forging obtained by the multi-pass forging deformation to 10℃ below the beta transus temperature to perform precision forging deformation, and the deformation amount of the precision forging deformation is 45%.

[0056] Step two, the titanium alloy bar obtained in step one is machined into an extrusion blank, and a jacketed extrusion is performed to obtain an extruded pipe blank;

[0057] The process of machining the bar into an extrusion blank is as follows: the bar is machined into an extrusion blank with an outer diameter of φ180 mm and an inner diameter of φ79 mm, and the outer diameter tolerance is -0.5 mm, and the extrusion blank is chamfered at one end with R15;

[0058] The process of jacketed extrusion is as follows:

[0059] Step 201, the extrusion blank is coated with asbestos and red copper to obtain a jacketed extrusion blank;

[0060] Step 202, the jacketed extrusion blank obtained in step 201 is heated to 20℃ above the β phase transition point in an induction heating furnace and held for 60 min;

[0061] Step 203, the jacketed extrusion blank after heating and holding in step 202 is placed on an extruder for extrusion, the extrusion cylinder size is an inner diameter of φ185 mm, the preheating temperature is 200℃, and a high-temperature lubricant is applied, the extrusion ratio is controlled to be 8.2, and the extrusion speed is 38 mm / s;

[0062] Step three, the extruded pipe blank obtained in step two is subjected to heat treatment to obtain a high-strength and tough corrosion-resistant titanium alloy pipe; the heat treatment includes solid solution heat treatment and aging heat treatment, wherein the solid solution heat treatment regime is: holding at 60℃ below the β phase transition point for 1h, and air cooling, and the aging heat treatment regime is: holding at 550℃ for 4h, and air cooling.

[0063] After detection, the titanium alloy pipe prepared in this embodiment has a yield strength of 921 MPa, an elongation of 12.5%, and an impact energy at -20℃ of 52.6J, and according to the NACE TM0177-2016 test standard, a stress corresponding to 76% of the nominal yield strength is applied in the test solution A, and after 720 hours, the high-strength corrosion-resistant titanium alloy pipe does not break.

[0064] Example 4

[0065] This embodiment includes the following steps:

[0066] Step one, a titanium alloy ingot is subjected to multiple forging deformation and one-time precision forging deformation to obtain a titanium alloy bar; the titanium alloy ingot is composed of the following components by mass percentage: Al 6.15%, Sn 2.0%, Zr 3.5%, Mo 1.0%, V 0.5%, Nb 2.0%, and the balance is Ti and unavoidable impurities;

[0067] The process of the multi-pass forging deformation is as follows: the titanium alloy ingot is heated to 90 DEG C above the beta transus temperature for one-pass three-way upsetting and drawing forging, the single deformation amount is 40%, then the deformed forging is heated to 60 DEG C above the beta transus temperature for one-pass three-way upsetting and drawing forging, the single deformation amount is 30%; then the deformed forging is heated to 10 DEG C above the beta transus temperature for two-pass three-way upsetting and drawing forging, the single deformation amount is 30%, and water cooling is performed after forging; then the deformed forging is heated to 15 DEG C below the beta transus temperature for one-pass conventional forging, the single deformation amount is 30%, and water cooling is performed after forging;

[0068] The process of the one-pass precision forging deformation is as follows: the titanium alloy forging obtained through the multi-pass forging deformation is heated to 10 DEG C below the beta transus temperature for precision forging deformation, and the deformation amount of the precision forging deformation is 46%;

[0069] Step two, the titanium alloy bar blank obtained in step one is machined into an extrusion blank, and a jacketed extrusion is performed to obtain an extruded pipe blank;

[0070] The process of machining the bar blank into an extrusion blank is as follows: the bar blank is machined into an extrusion blank with an outer diameter of 180 mm and an inner diameter of 79 mm, and the outer diameter tolerance is 0 mm, and the extrusion blank is chamfered at one end with R12;

[0071] The process of the jacketed extrusion is as follows:

[0072] Step 201, the extrusion blank is coated with asbestos and red copper to obtain a jacketed extrusion blank;

[0073] Step 202, the jacketed extrusion blank obtained in step 201 is heated to 10 DEG C above the beta transus temperature in an induction heating furnace and is kept for 60 min;

[0074] Step 203, the jacketed extrusion blank after heating and keeping in step 202 is placed on an extrusion machine for extrusion, the extrusion cylinder size is an inner diameter of 185 mm, the preheating temperature is 200 DEG C, and high-temperature lubricant is applied, the extrusion ratio is controlled to be 9.3, and the extrusion speed is 36 mm / s;

[0075] Step three, the extruded pipe blank obtained in step two is subjected to heat treatment to obtain a high-strength and high-toughness corrosion-resistant titanium alloy pipe; the heat treatment includes solid solution heat treatment and aging heat treatment, wherein the solid solution heat treatment system is: keeping at 70 DEG C below the beta transus temperature for 2 h and air cooling, and the aging heat treatment system is: keeping at 580 DEG C for 4 h and air cooling.

[0076] The titanium alloy pipe prepared in the embodiment is detected to have a yield strength of 913 MPa, an elongation of 16.5%, and an impact energy at-20℃ of 53.3 J. According to the test standard NACE TM0177-2016, the pipe is tested in test solution A under a stress corresponding to 76% of the nominal yield strength, and no fracture occurs after 720 hours.

[0077] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application. Any simple modification, change and equivalent variation of the above embodiments according to the technical essence of the present application are still within the protection scope of the technical scheme of the present application.

Claims

1. A method for preparing a high-strength, tough, and corrosion-resistant titanium alloy pipe, characterized in that: The method comprises the following steps: Step 1, sequentially subjecting a titanium alloy ingot to multi-fire forging deformation and a single fine forging deformation to obtain a titanium alloy bar blank; the titanium alloy ingot is composed of the following components by mass percentage: Al 6.0%-6.7%, Sn 0.5%-2.0%, Zr 3.5%-4.5%, Mo 1%-1.15%, V 0.5%-1.5%, Nb 2.0%-3.1%, and the balance is Ti and unavoidable impurities; The multi-fire forging deformation process is as follows: heating the titanium alloy ingot to a temperature 50°C to 90°C above the β phase transformation point, performing two-fire three-time reversing upsetting forging, with a single deformation of 30% to 40%; then heating the deformed forging to a temperature 10°C to 20°C above the β phase transformation point, performing two-fire three-time reversing upsetting forging, with a single deformation of 30%, and water cooling after forging; then heating the deformed forging to a temperature 10°C to 20°C below the β phase transformation point, performing one-fire conventional forging, with a single deformation of 30%, and water cooling after forging; The process of the single fine forging deformation is: heating the titanium alloy forging obtained by multiple forging deformation to a temperature 10°C to 20°C below the β phase transformation point and then performing fine forging deformation, wherein the deformation amount of the fine forging deformation is not less than 40%; Step 2: Mechanically process the titanium alloy bar obtained in step 1 into an extrusion billet, and perform sheath extrusion to obtain an extruded tube billet; the sheath extrusion process is as follows: Step 201: Coat the extruded blank with asbestos and copper to obtain a coated extruded blank; Step 202: heating the jacketed extrusion blank obtained in step 201 in an induction heating furnace and keeping the temperature for 60 minutes; the heating temperature is 10° C. below the β phase transition point temperature to 40° C. above the β phase transition point temperature; Step 203: Place the heated and heat-insulated jacketed extrusion blank in step 202 on an extruder for extrusion. The extrusion barrel has an inner diameter of 185 mm, a preheating temperature of 200° C., and is coated with a high-temperature lubricant. The extrusion ratio is controlled to be 7.3-10.1, and the extrusion speed is 35 mm / s-40 mm / s. Step 3: heat treating the extruded tube obtained in step 2 to obtain a high-strength, toughness, and corrosion-resistant titanium alloy tube; the yield strength of the titanium alloy tube is not less than 900 MPa, the elongation is not less than 10%, and the impact energy at -20°C is not less than 50 J. According to the NACETM0177-2016 test standard, a stress corresponding to 76% of the nominal yield strength is applied in test solution A for testing. After 720 hours, the high-strength, corrosion-resistant titanium alloy tube does not break.

2. The method for preparing a high-strength, toughness, corrosion-resistant titanium alloy pipe according to claim 1, characterized in that: The process of machining the rod blank into the extrusion blank in step 2 is as follows: the rod blank is machined into an extrusion blank with an outer diameter of φ181mm and an inner diameter of φ79mm, and the outer diameter tolerance is -1mm~0mm, and one end of the extrusion blank is chamfered R10~15.

3. The method for preparing a high-strength, toughness, corrosion-resistant titanium alloy pipe according to claim 1, characterized in that: The heat treatment in step 3 includes solution heat treatment and aging heat treatment, wherein the solution heat treatment system is: keeping at 50°C~80°C below the β phase transformation point for 1h~2h, air cooling, and the aging heat treatment system is: keeping at 550°C~600°C for 4h, air cooling.