High-strength plastic titanium-based composite ring-shaped part and preparation method and application thereof

Abstract

The application belongs to the technical field of metal material forming, and relates to a high-strength plastic titanium-based composite material ring-shaped piece and a preparation method and application thereof. The preparation method comprises the following steps: uniformly mixing titanium alloy powder and reinforcing phase powder, preparing a ring-shaped blank according to a process flow of "melting -> plasma rotating electrode atomization -> degassing and sealing welding -> hot isostatic pressing -> ring rolling", and finally performing annealing treatment on the ring-shaped blank to obtain a target ring-shaped piece. The application replaces the traditional laboratory small-batch ball milling method for preparing titanium-based composite material powder by using "large-batch mixing + vacuum induction melting rod preparation + plasma rotating electrode atomization method", so that the reinforcing phase can be introduced into the titanium matrix crystal and uniformly distributed, and the application is suitable for industrialized mass production requirements. The titanium-based composite material ring-shaped piece is prepared through the "powder metallurgy blank preparation + hot deformation" process, the size accuracy of powder metallurgy forming and the high efficiency of special-shaped ring rolling are utilized to achieve the effects of reducing the processing period, improving the material utilization rate and the forming rate.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal material forming, and relates to preparation of a titanium-based composite material ring-shaped piece, in particular to a high-strength and high-plasticity titanium-based composite material ring-shaped piece and a preparation method and application thereof. BACKGROUND

[0002] Titanium alloy ring-shaped pieces are widely used as key components of high-end equipment such as aircraft engines and spacecraft due to their high specific strength, corrosion resistance and high-temperature performance. However, with the continuous improvement of equipment performance requirements, the traditional titanium alloy ring-shaped pieces gradually expose the following technical bottlenecks: 1. The existing titanium alloy (such as Ti-6Al-4V) is prone to microstructure degradation in a high-temperature environment above 600℃, which leads to a significant decrease in creep resistance and fatigue strength; 2. The traditional forging + ring rolling process has limited ability to regulate the microstructure of the material, making it difficult to achieve grain refinement and isotropic optimization; 3. The introduction of external reinforcing phases (such as ceramic particles) often causes stress concentration due to interfacial reactions or uneven distribution, reducing the reliability of the material.

[0003] To address the above technical bottlenecks, existing technologies often optimize rolling process parameters or use β forging to improve microstructure uniformity, but they cannot break through the intrinsic performance limits of the material, and have problems such as high energy consumption, long cycle time and low material utilization.

[0004] Therefore, the present application is proposed. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide a high-strength and high-plasticity titanium-based composite material ring-shaped piece, a preparation method and application thereof.

[0006] To achieve the above purpose, the present application provides the following technical solutions:

[0007] In a first aspect, the present application provides a preparation method of a high-strength and high-plasticity titanium-based composite material ring-shaped piece. First, titanium alloy powder and reinforcing phase powder are uniformly mixed, then a ring-shaped blank is prepared according to the process flow of "melting → plasma rotating electrode atomization → degassing and sealing → hot isostatic pressing → ring rolling", and finally the target ring-shaped piece is prepared by annealing the ring-shaped blank; wherein the weight of the reinforcing phase powder is 0.1-1wt% of the total weight of the mixed powder after mixing.

[0008] Specifically, the specific steps of the preparation method are as follows:

[0009] Step 1, material selection and mixing: mixing the selected titanium alloy matrix powder and reinforcing phase powder to obtain a mixed powder;

[0010] Step 2, preparing titanium-based composite rod: placing the mixed powder in a vacuum induction furnace, and performing multiple melting in an inert gas atmosphere to obtain a titanium-based composite rod;

[0011] Step 3, powdering: based on the titanium-based composite rod, using a plasma rotating electrode atomization method to obtain a titanium-based composite material powder, and after screening, obtaining a target section powder for preparing a ring blank;

[0012] Step 4, powder loading: loading the target section powder into a ring-shaped package, and then performing degassing and sealing treatment;

[0013] Step 5, preparing ring blank: performing hot isostatic pressing treatment on the package with the target section powder after the degassing and sealing treatment to obtain a ring blank;

[0014] Step 6, multi-pass ring rolling: after heating and holding of the ring blank, performing multi-pass ring rolling to obtain a target ring blank; wherein the heating temperature is 900-980℃, and the holding time is 120-180min;

[0015] Step 7, heat treatment: performing heat treatment on the target ring blank to obtain a target ring-shaped part.

[0016] Further, low / medium / high temperature environment suitable titanium alloy powder and low / medium / high strength grade titanium alloy powder can be selected as the titanium alloy base powder, such as TC4 powder, TC11 powder, TC18 powder, Ti60 powder, etc., and nano-level carbon black powder, pure silicon powder or micron-level TiB2 powder can be selected as the reinforcing phase powder. The purity of the TC4 powder, TC11 powder, TC18 powder, Ti60 powder, carbon black powder, pure silicon powder and TiB2 powder is not less than 95%, and the particle size of the titanium alloy base powder is 53-106μm, and the particle size of the reinforcing phase powder is 20nm-1μm.

[0017] According to the application environment temperature, the titanium alloy powder is divided as follows: medium temperature environment suitable titanium alloy refers to the general use temperature of 350-500℃, and high temperature environment suitable titanium alloy refers to the general use temperature of 500-650℃; according to the strength grade, the titanium alloy is divided as follows: medium strength titanium alloy refers to the tensile strength of about 800-1000MPa, high strength titanium alloy refers to the tensile strength of about 1000-1250MPa, and super high strength titanium alloy refers to the tensile strength higher than 1250MPa.

[0018] Further, the reinforcing phase powder can be selected from one of the following components, and the weight percentage in the mixed powder is as follows: carbon black powder 0.3-1.0wt%, TiB2 powder 0.3-0.5wt%, and pure silicon powder 0.1-0.3wt%.

[0019] Further, in step 6, the multi-pass ring rolling is specifically as follows:

[0020] First, 2-3 passes of ring rolling are performed, with a single deformation of 8-12%, a strain rate of 0.02-0.1 s -1 , a holding time of 20-60 min, and a total deformation of 20-30%;

[0021] Then, 3-4 passes of ring rolling are performed, with a single deformation of 5-10%, a strain rate of 0.02-0.05 s -1 , a holding time of 20-40 min, and a total deformation of 20-30%;

[0022] Further, in step 5, the temperature of the hot isostatic pressing is 890-960℃, the pressure is 130-200 MPa, and the holding time is 1-3 h.

[0023] Further, in step 4, the design parameters of the ring-shaped sleeve are as follows:

[0024] The inner diameter of the ring-shaped sleeve is 55-80% of the inner diameter of the target ring, the outer diameter is 120-130% of the outer diameter of the target ring, the height is 150-180% of the height of the target ring, and the thickness of the ring-shaped sleeve is 3-8 mm.

[0025] Further, in step 4, the degassing is performed by heating, with the following parameters: a vacuum degree of ≤5×10 - 3 Pa, a heating temperature of 400-500℃, and a holding time of 6-8 h.

[0026] Further, in step 3, the plasma rotating electrode atomization process has the following parameters: a vacuum degree of ≤1.1×10 -2 Pa, a voltage of 60-85 V, a current of 1700±100 A, and a rotation speed of 28000±500 r / min; the particle size range of the target segment powder is 75-150 μm, and the median diameter D50 of the laser particle size distribution is 100-120 μm.

[0027] Further, in step 2, the melting has the following parameters: a vacuum degree of ≤5×10 -3 Pa, a melting temperature of 1650-1850℃, and a melting time of 25-35 min.

[0028] Further, in step 1, the mixing is performed in a vacuum environment using a mixer, with a vacuum degree of ≤1.1×10 -2Pa, the rotation speed is 120-150 r / min, and the mixing time is 30-35 h; in the mixing of the titanium alloy base powder and the reinforcing phase powder: the titanium alloy powder and half of the reinforcing phase powder are first mixed uniformly in the mixer, and then the remaining reinforcing phase powder is added and mixed again uniformly, and the protective gas is argon.

[0029] Further, in step 7, the target ring blank is subjected to homogenization annealing treatment, the annealing temperature is 600-860 DEG C, the holding time is 1-5 h, and the cooling mode is water quenching or air cooling.

[0030] In a second aspect, the application further provides a high strength and plasticity titanium-based composite ring part prepared based on the preparation method.

[0031] In addition, the application further provides an application of the titanium-based composite ring part for aviation structures under different service conditions.

[0032] Compared with the prior art, the technical scheme provided by the application has the following beneficial effects:

[0033] 1) The introduction of the in-situ self-grown reinforcing phase in the titanium-based composite material can produce strong interfacial bonding with the titanium alloy base, and this structure can effectively prevent crystal slip and intergranular slip, thereby significantly improving the yield strength of the material. Moreover, due to the existence of the reinforcing phase and the strong interfacial bonding, the titanium-based composite material can more effectively resist fatigue damage when subjected to external force. In addition, the existence of the reinforcing phase can absorb and disperse external stress, prevent further expansion of internal cracks of the material, and improve the impact resistance of the material;

[0034] 2) The preparation method is applied in the near-net forming powder metallurgy preparation process, the powder is not easy to be contaminated in the process, and the powder does not need to be cooled after reaching the molten state, thereby reducing the secondary segregation of elements, and the structure is more uniform compared with the casting / forging process, and can withstand lower temperature and higher strain rate without cracking;

[0035] 3) The application replaces the traditional laboratory small-batch ball milling method for preparing titanium-based composite material powder by using the "large-batch mixing + vacuum induction melting rod + plasma rotating electrode atomization method", which can realize the introduction of the reinforcing phase into the titanium base and uniform distribution, and is suitable for industrialized mass production to meet the actual industrialization needs; the titanium-based composite material ring part is prepared by the "powder metallurgy preparation + hot deformation" process, which can utilize the size accuracy of powder metallurgy forming and the high efficiency of special-shaped ring rolling to achieve the effects of reducing the processing period, improving the material utilization rate and the forming rate.

[0036] In summary, the application innovatively proposes a short-process, high-strength and plastic titanium-based composite ring preparation method of four-in-one: titanium alloy matrix powder and reinforcing phase powder are mixed, and a composite bar is prepared by induction smelting, the composite bar is used as a consumable electrode for plasma rotating electrode atomization after precision turning, the centrifugal force generated by high-speed rotation of the electrode (28000-32000 rpm) refines the molten droplets, and argon quenching is used to form titanium-based composite powder with high sphericity; the obtained titanium-based composite powder is loaded into a ring-shaped sleeve for degassing welding, and after completion, hot isostatic pressing densification is performed to prepare a blank, and a ring rolling process is combined, a matching relationship between roller speed ratio (roller strain rate) and deformation is established, the reinforcing phase is induced to arrange along the grain boundary, and gradient cooling is introduced in the rolling process combined with deformation heat treatment technology, to promote the synergistic occurrence of dynamic recrystallization and beta to alpha phase change, and finally obtain a dual-mode structure of "equiaxed alpha + fibrous / particle-shaped reinforcement". BRIEF DESCRIPTION OF DRAWINGS

[0037] The accompanying drawings, which are incorporated into and form part of the specification, illustrate the present application and, together with the description, serve to explain the principles of the application.

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, those skilled in the art can obtain other drawings from these drawings without any creative effort.

[0039] Figure 1 A flow chart of the preparation method of the high-strength and plastic titanium-based composite ring provided by the present application is shown in the figure.

[0040] Figure 2 A manufacturing process flow of the high-strength and plastic titanium-based composite ring provided by the present application is shown in the figure.

[0041] Figure 3 A three-dimensional thermal-mechanical coupling finite element model of the titanium-based composite process provided by the present application is shown in the figure.

[0042] Figure 4 A kinematic relationship diagram of each roller in the titanium-based composite ring process provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0043] The exemplary embodiments will be described in detail hereinafter, and the embodiments described in the following exemplary embodiments do not represent all the embodiments consistent with the present application. Instead, they are only examples consistent with some aspects of the present application as described in the appended claims.

[0044] The application takes low / medium / high temperature environment applicable titanium alloy and low / medium / high strength level titanium alloy as base powder, introduces reinforcing phase powder, combines powder metallurgy and hot deformation process, and cooperates with heat treatment system to control volume fraction of equiaxed alpha phase, lath alpha phase and transformed beta organization; the strong pinning effect of in-situ self-grown reinforcing phase and the hindering effect of grain refinement on dislocation after part of grains are recrystallized in ring rolling process make the material strength be significantly improved without too much sacrifice of the elongation of the material; the high strength near-beta titanium alloy cooperates with solid solution and aging process to further control the proportion and morphology of phases to meet the differentiated demand for mechanical properties of the ring-shaped parts under different working service conditions. In general, the application obtains the titanium-based composite ring-shaped part with large size, uniform structure and excellent mechanical properties by the above short process, high precision, less processing and high utilization rate process, thereby effectively solving the problems of long production cycle and low mechanical properties of the traditional forged ring.

[0045] In order to make the skilled in the art better understand the technical solutions of the application, the application will be further described in detail below in combination with the drawings and examples.

[0046] Referring to Figures 1-2 The application provides a preparation method of a high strength and plastic titanium-based composite ring-shaped part. First, titanium alloy powder and reinforcing phase powder are uniformly mixed, then a ring-shaped blank is prepared according to the process flow of "melting → plasma rotating electrode atomization → degassing and sealing → hot isostatic pressing → ring rolling", and finally the target ring-shaped part is prepared by annealing the ring-shaped blank. The weight of the reinforcing phase powder is 0.1-1wt% of the total weight of the uniformly mixed powder.

[0047] Further, the specific steps of the preparation method are as follows:

[0048] Step 1, material selection and mixing: the selected titanium alloy base powder and reinforcing phase powder are mixed to obtain mixed powder;

[0049] Step 2, preparation of titanium-based composite rod: the mixed powder is placed in a vacuum induction furnace and is subjected to multiple melting in an inert gas atmosphere to obtain a titanium-based composite rod;

[0050] Step 3, powder preparation: based on the titanium-based composite rod, a titanium-based composite material powder is prepared by using the plasma rotating electrode atomization method, and after screening, the target section powder for preparing the ring-shaped blank is obtained;

[0051] Step 4, powder loading: the target section powder is loaded into a ring-shaped package for degassing and sealing treatment;

[0052] Step 5, preparation of ring-shaped blank: the package with the target section powder after the degassing and sealing treatment is subjected to hot isostatic pressing treatment to obtain a ring-shaped blank;

[0053] Step 6, multi-pass ring rolling: after the ring blank is heated and kept, the target ring rolling piece is obtained by multi-pass ring rolling; wherein the heating temperature is 900-980℃, and the holding time is 120-180min; the multi-pass ring rolling adopts a titanium-based composite ring piece process, and the kinematics relationship of the rollers in the process is as shown in Figure 4

[0054] Step 7, heat treatment: the target ring rolling piece is subjected to heat treatment to obtain a target ring piece.

[0055] Example 1

[0056] The embodiment provides a preparation method of a high-strength and high-plasticity titanium-based composite ring piece, and comprises the following steps:

[0057] Step 1, material selection and mixing: the selected titanium alloy base powder and the reinforcing phase powder are mixed to obtain a mixed powder, which can be subdivided into two steps:

[0058] Material selection: micron-level α+β two-phase TC4 titanium alloy is selected as the titanium alloy base powder, and the particle size is 53-106μm; and nanometer-level carbon black powder is selected as the reinforcing phase (precursor) powder, the particle size is 20nm, and the purity is 99.9%; and the weight of the nanometer-level carbon black powder is 0.3-1.0wt% of the total weight of the mixed powder after mixing;

[0059] Powder mixing: the selected titanium alloy base powder and half of the reinforcing phase powder are placed in a mixer and mixed uniformly, and the other half of the reinforcing phase powder is added and mixed uniformly again, the protective gas is argon, the vacuum degree is ≤1.1×10 -2 Pa, the rotation speed is 120r / min, and the mixing time is 35h;

[0060] Step 2, preparation of titanium-based composite rod: the mixed powder is placed in a vacuum induction furnace, and is subjected to melting in a high-purity argon protective atmosphere; the vacuum degree of the melting chamber is ≤5×10 -3 Pa, the melting temperature is 1670-1690℃, the melting time is 25min, the melting is repeated for 3 times, and the titanium-based composite rod is obtained after cooling to room temperature;

[0061] Step 3, powder preparation: based on the titanium-based composite rod, a titanium-based composite material powder is prepared by using a plasma rotating electrode atomization method, a vacuum degree is ≤1.1×10 -2 Pa, the voltage is 60V, the current is 1600A, and the rotation speed is 28000r / min; after screening, the powder with a particle size range of 75-150μm and a laser particle size distribution median diameter D50 of 100μm is selected for subsequent preparation of a ring blank; and the powder composition should meet the requirements of GB / T 3620.1-2016, wherein the oxygen content in the powder element composition is 75ppm, and the nitrogen content is 18ppm.​

[0062] Step 4, powder loading: the target segment powder is loaded into an annular jacket for heating, degassing, impurity removal and sealing treatment; the jacket is made of 45 steel, with an inner diameter of about 40 mm, an outer diameter of about 128 mm, a height of about 32 mm and a wall thickness of about 4.5 mm; during the heating and degassing process, the vacuum degree is required to be ≤5×10 -3 Pa, the heating temperature is 420℃, and after 7h of heat preservation, five passes of sealing treatment are performed;

[0063] Step 5, preparation of annular blank: the jacket after degassing and sealing treatment and containing the target segment powder is subjected to hot isostatic pressing densification sintering treatment to obtain a TC4-based annular blank, the hot isostatic pressing treatment temperature is 910-930℃, the pressure is 135±5MPa, the heat preservation time is 150min, and the furnace cooling speed is 10℃ / min;

[0064] Step 6, multi-pass ring rolling: the TC4-based annular blank is heated and preserved, and then multi-pass ring rolling is performed to obtain the target ring rolling piece; wherein,

[0065] the heating temperature is 950℃, the heat preservation time is 150min, after the heating and heat preservation are completed, the TC4-based annular blank is taken out to perform the first pass of ring rolling to obtain an intermediate ring piece, the rolling deformation amount is 10%, and the rolling strain rate is 0.05s -1 ;

[0066] Due to the strong pinning effect of the titanium-based composite material reinforcing phase on the grain boundary, the ring rolling must be performed in a small amount and multiple passes. After the first pass of ring rolling is completed, the intermediate ring piece is taken out after 40min of heat preservation to remove part of the residual stress, and then the second pass of ring rolling is performed, the rolling deformation amount is 10%, and the rolling strain rate remains unchanged. The third pass of ring rolling is performed under the same parameters;

[0067] The total rolling deformation amount of the first three passes is 30%. To avoid cracking, three more passes of ring rolling with small deformation amount are required, the heat preservation time is 40min, the deformation amount is 7%, and the strain rate is 0.03s -1 . The rolling deformation amount of the last three passes is 21%. The ring rolling process has a total of 6 passes, and the total deformation amount is 51%. Finally, a target annular blank with a specification of φ118×φ35×26mm is obtained.

[0068] Step 7, heat treatment: the target annular blank is subjected to homogenizing annealing treatment at a temperature of 750℃ for 120min, and the cooling method is air cooling;

[0069] Step 8, machining: the target annular blank after annealing treatment is subjected to machining treatment, and finally a TC4-based composite material annular piece with a specification of φ100×φ50×20mm is obtained.

[0070] Example 2

[0071] The embodiment provides a preparation method of a high-strength plastic titanium-based composite ring-shaped piece, and comprises the following steps:

[0072] Step 1, material selection and mixing: the selected titanium alloy base powder and the reinforcing phase powder are mixed to obtain a mixed powder, which can be subdivided into two steps:

[0073] Material selection: micron-level α+β two-phase TC11 titanium alloy is selected as the titanium alloy base powder, the particle size of which is 53-106 μm, and nano-level TiB2 powder is selected as the reinforcing phase (precursor) powder, the particle size of which is 40 nm and the purity of which is 99.9%; and the weight of the nano-level TiB2 powder is 0.3-0.5 wt% of the total weight of the mixed powder after mixing;

[0074] Powder mixing: the selected titanium alloy base powder and half of the reinforcing phase powder are placed in a mixer and mixed uniformly, and the other half of the reinforcing phase powder is added and mixed uniformly again, the protective gas is argon, the vacuum degree is ≤1.1×10 -2 Pa, the rotating speed is 130 r / min, and the mixing time is 32 h;

[0075] Step 2, preparation of a titanium-based composite rod: the mixed powder is placed in a vacuum induction furnace and is subjected to melting in a high-purity argon protective atmosphere; the vacuum degree of the melting chamber is ≤5×10 -3 Pa, the melting temperature is 1710-1730 ℃, the melting time is 35 min, the melting is repeated twice, and the titanium-based composite rod is obtained after cooling to room temperature and processing;

[0076] Step 3, powder preparation: based on the titanium-based composite rod, a titanium-based composite material powder is prepared by using a plasma rotating electrode atomization method, a vacuum degree is ≤1.1×10 -2 Pa, the voltage is 78 V, the current is 1750 A, and the rotating speed is 30000 r / min, the powder with a particle size range of 75-150 μm and a median diameter D50 of 110 μm in a laser particle size distribution is selected after screening, and the powder composition meets the requirements of GB / T 3620.1-2016, wherein the oxygen content in the powder element composition is 80 ppm, and the nitrogen content is 21 ppm;

[0077] Step 4, powder loading: the target section powder is loaded into a ring-shaped package, and heating, degassing, impurity removal and sealing welding treatment are performed; the material for manufacturing the ring-shaped package is selected from 45 steel, the inner diameter of the package is about 40 mm, the outer diameter of the package is about 128 mm, the height of the package is about 32 mm, and the wall thickness of the package is about 4.5 mm; in the process of heating and degassing, the vacuum degree is required to be ≤5×10 -3 Pa, the heating temperature is 400 ℃, and five passes of sealing welding treatment are performed after 8 h of heat preservation;

[0078] Step 5, preparation of the ring blank: the capsule containing the target segment powder after the degassing and sealing treatment is subjected to a hot isostatic pressing densification sintering treatment to obtain a TC11-based ring blank, the temperature of the hot isostatic pressing treatment is 950±10℃, the pressure is 145±5MPa, the holding time is 180min, and the in-furnace cooling speed is 10℃ / min;

[0079] Step 6, multi-pass ring rolling: the TC11-based ring blank is subjected to multi-pass ring rolling after heating and holding to obtain a target ring rolling piece; wherein,

[0080] The heating temperature is 980℃, the holding time is 150min, and after the heating and holding is completed, the TC11-based ring blank is taken out to perform the first-pass ring rolling to obtain an intermediate ring piece, the rolling deformation is 8%, and the rolling strain rate is 0.02s -1 ;

[0081] Due to the strong pinning effect of the titanium-based composite material reinforcing phase on the grain boundary, the ring rolling must be performed multiple times in small amounts, after the first-pass ring rolling is completed, the intermediate ring piece is taken out after holding for 60min to remove part of the residual stress, and then the second-pass ring rolling is performed, the rolling deformation is 8%, and the rolling strain rate remains unchanged; the third-pass ring rolling is performed under the same parameters;

[0082] The total rolling deformation of the first three passes is 24%, to avoid cracking, subsequent small deformation ring rolling needs to be performed three more times, the holding time is 30min, the deformation is 6%, and the strain rate is 0.03s -1 , and the rolling deformation of the last three passes is 18%; the ring rolling process has a total of 6 passes, and the total deformation is 42%, and finally a target ring blank with a specification of φ118×φ35×26mm is obtained;

[0083] Step 7, heat treatment: the target ring blank is subjected to homogenization annealing treatment, the temperature is 850℃, the holding time is 60min, and the cooling method is air cooling;

[0084] Step 8, machining: the target ring blank after annealing treatment is subjected to machining treatment, and finally a TC11-based composite material ring piece with a specification of φ100×φ50×20mm is obtained.

[0085] Example 3

[0086] The embodiment provides a preparation method of a high-strength and high-plasticity titanium-based composite material ring piece, comprising the following steps:

[0087] Step 1, material selection and mixing: the selected titanium alloy base powder and reinforcing phase powder are mixed to obtain a mixed powder, which can be subdivided into two steps:

[0088] Material selection: micron-grade near-beta TC18 titanium alloy is selected as the titanium alloy base powder, with a particle size of 53-106 μm, and micron-grade pure silicon powder is selected as the reinforcing phase powder, with a particle size of 1 μm and a purity of 99.9%; the weight of the micron-grade pure silicon powder is 0.1-0.3 wt% of the total weight of the mixed powder after mixing;

[0089] Mixing of powder: the selected titanium alloy base powder and half of the reinforcing phase powder are placed in a mixer and mixed uniformly, and the other half of the reinforcing phase powder is added and mixed again, the protective gas is argon, the vacuum degree is ≤1.1×10 -2 Pa, the rotation speed is 140 r / min, and the mixing time is 31 h;

[0090] Step 2, preparation of titanium-based composite rod: the mixed powder is placed in a vacuum induction furnace and melted in a high-purity argon protective atmosphere; the vacuum degree of the melting chamber is ≤5×10 -3 Pa, the melting temperature is 1720±10℃, the melting time is 35 min, the melting is repeated for 3 times, and the titanium-based composite rod is obtained after cooling to room temperature and processing;

[0091] Step 3, powder preparation: based on the titanium-based composite rod, a plasma rotating electrode atomization method is used to prepare titanium-based composite material powder with a vacuum degree of ≤1.1×10 -2 Pa, a voltage of 85 V, a current of 1650 A, and a rotation speed of 31000 r / min; after screening, the powder with a particle size range of 75-150 μm and a laser particle size distribution median diameter D50 of 110 μm is selected for subsequent preparation of ring-shaped blank; the powder composition shall meet the requirements of GB / T 3620.1-2016, wherein the oxygen content in the powder element composition is 75 ppm, and the nitrogen content is 15 ppm;

[0092] Step 4, powder loading: the target section powder is loaded into a ring-shaped jacket for heating, degassing, impurity removal, and sealing treatment; the jacket is made of 45 steel, with an inner diameter of about 40 mm, an outer diameter of about 128 mm, a height of about 32 mm, and a wall thickness of about 4.5 mm; during the heating and degassing process, the vacuum degree is required to be ≤5×10 -3 Pa, the heating temperature is 420℃, and the five-pass sealing treatment is carried out after 7 h of heat preservation;

[0093] Step 5, preparation of ring-shaped blank: the jacket with the target section powder after degassing and sealing treatment is subjected to hot isostatic pressing densification sintering treatment to obtain a TC18-based ring-shaped blank; the hot isostatic pressing treatment temperature is 890-910℃, the pressure is 140±5 MPa, the holding time is 60 min, and the in-furnace cooling speed is 10℃ / min;

[0094] Step 6, multi-pass ring rolling: after the TC18 base ring blank is heated and kept, the target ring rolling piece is obtained by multi-pass ring rolling; wherein,

[0095] The heating temperature is 900℃, the holding time is 120min, and after the heating and holding is finished, the TC18 base ring blank is taken out to perform the first-pass ring rolling to obtain an intermediate ring piece, the rolling deformation is 12%, and the rolling strain rate is 0.1s -1 ;

[0096] Due to the strong pinning effect of the titanium-based composite material on the grain boundary, the ring rolling needs to be performed for a small number of times. After the first-pass ring rolling is finished, the intermediate ring piece is taken out after being kept for 20min to remove part of the residual stress, and then the second-pass ring rolling is performed, the rolling deformation is 24%, and the rolling strain rate is unchanged;

[0097] The total rolling deformation of the first two passes is 24%. To avoid cracking, the ring rolling needs to be performed for four more times with small deformation. The holding time is 40min, the deformation is 7%, and the strain rate is 0.05s -1 . The rolling deformation of the last four passes is 28%. The ring rolling process has a total of 6 passes, and the total deformation is 52%. Finally, the target ring blank with a size of φ118xφ35x26mm is obtained;

[0098] Step 7, heat treatment: the target ring blank is subjected to solid solution and aging treatment. The solid solution treatment system is 860℃ / 2h / water cooling, and the aging treatment system is 750℃ / 4h / air cooling;

[0099] Step 8, machining: the target ring blank after annealing treatment is subjected to machining treatment, and finally the TC18-based composite ring piece with a size of φ100xφ50x20mm is obtained.

[0100] Example 4

[0101] The embodiment provides a preparation method of a high-strength and high-plasticity titanium-based composite ring piece, comprising the following steps:

[0102] Step 1, material selection and mixing: the selected titanium alloy base powder and reinforcing phase powder are mixed to obtain a mixed powder, which can be realized in two steps:

[0103] Material selection: micron-level near-alpha Ti60 titanium alloy is selected as the titanium alloy base powder, the particle size is 53-106μm, and nano-level TiB2 powder is selected as the reinforcing phase powder, the particle size is 40nm, and the purity is 99.9%. The weight of the nano-level TiB2 powder is 0.1-0.3wt% of the total weight of the mixed powder after mixing;

[0104] Mixing powder: the selected titanium alloy matrix powder and half of the reinforcing phase powder are placed in a mixer to mix uniformly, and the other half of the reinforcing phase powder is added again to mix uniformly again, the protective gas is argon, the vacuum degree is ≤1.1×10 -2 Pa, the rotation speed is 150 r / min, and the mixing time is 30 h;

[0105] Step 2, preparation of titanium-based composite rod: the mixed powder is placed in a vacuum induction furnace, and is melted in a high-purity argon protective atmosphere; the vacuum degree of the melting chamber is ≤5×10 -3 Pa, the melting temperature is 1800±50℃, the melting time is 25 min, the melting is repeated for 3 times, and the titanium-based composite rod is obtained after cooling to room temperature;

[0106] Step 3, powder preparation: based on the titanium-based composite rod, the titanium-based composite material powder is prepared by using a plasma rotating electrode atomization method, a vacuum degree is ≤1.1×10 -2 Pa, a voltage is 75 V, a current is 1800 A, and a rotation speed is 32000 r / min; after screening, the powder with a particle size range of 75-150 μm and a laser particle size distribution median diameter D50 of 120 μm is selected for subsequent preparation of the annular blank; the powder composition should meet the requirements of GB / T 3620.1-2016, wherein the oxygen content in the powder element composition is 78 ppm, and the nitrogen content is 18 ppm;

[0107] Step 4, powder loading: the target section powder is loaded into an annular jacket for heating, degassing, impurity removal and sealing treatment; the jacket is made of 45 steel, the inner diameter of the jacket is about 40 mm, the outer diameter of the jacket is about 128 mm, the height of the jacket is about 32 mm, and the wall thickness of the jacket is about 4.5 mm; during the heating and degassing process, the vacuum degree is required to be ≤5×10 -3 Pa, the heating temperature is 420℃, and the sealing treatment is performed after 7 h of heat preservation;

[0108] Step 5, preparation of annular blank: the jacket with the target section powder after the degassing and sealing treatment is subjected to hot isostatic pressing densification sintering treatment to obtain a Ti60-based annular blank; the hot isostatic pressing treatment temperature is 940-960℃, the pressure is 140±5 MPa, the heat preservation time is 180 min, and the furnace cooling speed is 10℃ / min;

[0109] Step 6, multi-pass ring rolling: the Ti60-based annular blank is heated and held to perform multi-pass ring rolling to obtain a target ring rolling piece; wherein,

[0110] the heating temperature is 950℃, the heat preservation time is 150 min, the Ti60-based annular blank is taken out after the heating and heat preservation are completed, the first-pass ring rolling is performed to obtain an intermediate ring piece, the rolling deformation is 10%, and the rolling strain rate is 0.05s -1 ;

[0111] Due to the strong pinning effect of the titanium-based composite reinforcing phase to the grain boundary, the ring rolling is performed for a small number of times, after the first pass of ring rolling, the temperature is kept for 40 min to remove part of the residual stress, at this time, the intermediate ring is taken out to perform the second pass of ring rolling, the rolling deformation is 10%, and the rolling strain rate is unchanged; the third pass of ring rolling is performed with the same parameters;

[0112] The total rolling deformation of the first three passes is 30%, to avoid cracking, three times of small deformation ring rolling need to be further performed, the holding time is 40 min, the deformation is 7%, and the strain rate is 0.03 s -1 The rolling deformation of the last three passes is 21%; the ring rolling process has a total of 6 passes, and the total deformation is 51%, and finally the target ring blank φ120*φ36*28 mm is obtained;

[0113] Step 7, heat treatment: the target ring blank is subjected to homogenizing annealing treatment, the temperature is 600 DEG C, the holding time is 300 min, and the cooling mode is air cooling;

[0114] Step 8, machining: the target ring blank after annealing treatment is subjected to machining treatment, and finally the Ti60-based composite ring blank with a specification of φ100*φ50*20 mm is obtained.

[0115] The titanium-based composite ring blanks of different grades prepared in the above embodiments 1-4 are subjected to related mechanical property experiments, and the experiments show that the tensile strength of the target ring blank at room temperature is increased to 1450 MPa (increased by 35%-45% compared with the traditional titanium alloy), the high-temperature strength retention rate at 800 DEG C is more than 75%, and the fracture toughness is increased by 20%-30%. In addition, as shown in the figure, by establishing a "reinforcing phase distribution-process control-performance mapping" model, the radial / axial mechanical property gradient of the target ring blank can be precisely controlled, so as to meet the dual requirements of "load reduction" of the aircraft engine casing and other components. Figure 3

[0116] ​In summary, the preparation method provided by the application innovates from aspects of material design, preparation process and forming technology: ① the ceramic reinforcing phase is successfully introduced into the titanium alloy matrix by using the process of "mixing-vacuum induction melting to prepare rods-plasma rotating electrode powdering", and the titanium-based composite powder with nanoscale reinforcing phase in the interior can be obtained due to the faster cooling speed and smaller reinforcing phase size; ② the in-situ self-reinforcing technology (such as the TiBw / Ti system) is adopted to generate nanoscale TiB whiskers through Ti-TiB2 in-situ reaction, so that the good interface compatibility of the reinforcing phase and the matrix is realized, and the interface pollution problem of the traditional external reinforcing body is avoided; ③ the combined preparation process of "powder metallurgy + ring rolling" is developed, and the three-dimensional uniform dispersion of the reinforcing phase is ensured by adjusting the powder particle size distribution and sintering parameters; ④ the small variable multi-pass rolling process is used to promote the directional arrangement of the reinforcing phase during the ring rolling forming stage, and the synergistic optimization of fine-grain strengthening and reinforcing phase orientation is realized through dynamic recrystallization.

[0117] The whole preparation process has the advantages of short time consumption, high efficiency, high precision and less processing, greatly improves the material utilization rate, can be applied to industrialized mass production, and is beneficial to quickly preparing the high-performance titanium-based composite material ring piece. Specifically, the application compresses the traditional ring piece production process to five passes through the deep coupling of "material-process-forming", improves the material utilization rate from 42% to 80%, reduces the machining allowance by more than 60%, and significantly enhances the mechanical properties, with the room temperature yield strength improved by 40% and the fracture toughness increased by 25%. The application has significant engineering application value.

[0118] The above description is merely a specific implementation of the application, which enables those skilled in the art to understand or implement the application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application.

[0119] It should be understood that the application is not limited to the above described and that various modifications and changes can be made without departing from the scope thereof. The scope of the application is limited only by the claims appended hereto.

Claims

1. A method for preparing a high-strength titanium-based composite ring-shaped part, characterized in that, First, titanium alloy powder and reinforcing phase powder are mixed evenly. Then, an annular billet is prepared according to the process flow of "melting → plasma rotating electrode atomization → degassing and sealing → hot isostatic pressing → ring rolling". Finally, the annular billet is annealed to obtain the target annular part. The weight of the reinforcing phase powder is 0.1~1wt% of the total weight of the mixed powder after uniform mixing. The reinforcing phase powder can be selected from one of the following components, and the weight percentages in the mixed powder are as follows: carbon black powder 0.3~1.0wt%, TiB2 powder 0.3~0.5wt%, pure silicon powder 0.1~0.3wt%. The specific steps of the preparation method are as follows: Step 1, Material Selection and Mixing: The selected titanium alloy matrix powder and reinforcing phase powder are mixed to obtain a mixed powder; Step 2: Preparation of titanium-based composite rods: The mixed powder is placed in a vacuum induction furnace and smelted multiple times in an inert gas atmosphere to obtain titanium-based composite rods; Step 3, Powder preparation: Based on the titanium-based composite rod, titanium-based composite material powder is prepared by plasma rotating electrode atomization method, and after sieving, the target segment powder for preparing the ring-shaped billet is obtained. Step 4, Powder loading: After loading the target segment powder into the annular sleeve, degassing and sealing are performed; Step 5: Preparation of ring-shaped billet: The casing containing the target segment powder after degassing and sealing treatment is subjected to hot isostatic pressing to obtain the ring-shaped billet; Step 6, multi-pass ring rolling: After heating and holding the ring billet at a certain temperature, multi-pass ring rolling is performed to obtain the target ring billet; wherein, the heating temperature is 900~980℃ and the holding time is 120~180min; Step 7, Heat treatment: The target annular blank is subjected to heat treatment to obtain the target annular part.

2. The method for preparing the high-strength titanium-based composite ring part according to claim 1, characterized in that, In step 6, the multi-pass ring rolling specifically involves: First, perform 2-3 passes of ring rolling, with a single deformation of 8%-12% and a strain rate of 0.02-0.1 s⁻¹. -1 The heat preservation time is 20~60 minutes, and the total deformation is 20%~30%; Then perform 3 to 4 more ring rolling passes, with a single deformation of 5% to 10% and a strain rate of 0.02 to 0.05 s. -1 The heat preservation time is 20~40 minutes, and the total deformation is 20%~30%.

3. The method for preparing the high-strength titanium-based composite ring part according to claim 1, characterized in that, In step 5, the temperature of the hot isostatic pressing treatment is 890~960℃, the pressure is 130~150MPa, and the holding time is 1~3h.

4. The method for preparing the high-strength titanium-based composite ring part according to claim 1, characterized in that, In step 4, The design parameters of the annular sleeve are as follows: the inner diameter of the annular sleeve is 55%~80% of the inner diameter of the target annular part, the outer diameter is 120%~130% of the outer diameter of the target annular part, the height is 150%~180% of the height of the target annular part, and the thickness of the annular sleeve is 3~8mm. Degassing is performed using heating, with the following parameters: vacuum degree ≤ 5 × 10⁻⁶. -3 Pa, heating temperature is 400~500℃, and holding time is 6~8h.

5. The method for preparing the high-strength titanium-based composite ring part according to claim 1, characterized in that, In step 3, the relevant parameters for the plasma rotating electrode atomization powder production process are as follows: vacuum degree ≤ 1.1 × 10⁻⁶ -2 Pa, voltage 60~85V, current 1700±100A, speed 28000±500 r / min.

6. The method for preparing the high-strength titanium-based composite ring part according to claim 1, characterized in that, In step 2, the relevant parameters for the smelting are as follows: vacuum degree ≤ 5 × 10⁻⁶ -3 Pa, melting temperature is 1650~1850℃, melting time is 25~35min.

7. The method for preparing the high-strength titanium-based composite ring part according to claim 1, characterized in that, In step 1, the mixing is carried out mechanically in a vacuum environment using a mixer, with a vacuum degree ≤ 1.1 × 10⁻⁶. -2 Pa, rotation speed of 120~150 r / min, mixing time of 30~35 h.

8. A high-strength titanium-based composite ring-shaped part prepared by the preparation method according to any one of claims 1 to 7, characterized in that, The mechanical properties of the target ring component are improved by 35% to 45% in terms of room temperature yield strength and 20% to 30% in terms of fracture toughness compared to room temperature.

9. An application of the preparation method according to any one of claims 1 to 7 in the preparation of titanium-based composite ring parts for aerospace structural components under different service conditions.

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