High-strength plastic titanium-based composite material annular part as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of metal material forming, and relates to a high-strength plastic titanium-based composite material annular part and a preparation method and application thereof. The preparation method comprises the following steps: firstly, uniformly mixing titanium alloy powder and reinforced phase powder, then preparing an annular blank according to the technological process of smelting, plasma rotating electrode atomization, degassing seal welding, hot isostatic pressing and ring rolling, and finally, annealing the annular blank to prepare the target annular part. According to the method, the titanium-based composite material powder is prepared by replacing a traditional laboratory small-batch ball milling method with a large-batch mixing method, a vacuum induction melting rod manufacturing method and a plasma rotating electrode atomization method, a reinforced phase can be introduced into a titanium matrix crystal and uniformly distributed, and the method is suitable for industrial large-batch production requirements; the titanium-based composite material annular part is prepared through the technology of powder metallurgy blank making and thermal deformation, and the effects of shortening the machining period and improving the material utilization rate and the forming rate are achieved through the precise size of powder metallurgy forming and the high efficiency of special-shaped ring rolling.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal material forming, relates to the preparation of titanium matrix composite rings, and particularly relates to a high-strength and high-ductility titanium matrix composite ring and its preparation method and application. Background Art

[0002] Titanium alloy ring rolled parts, as key components of high-end equipment such as aero-engines and aerospace vehicles, are widely used due to their high specific strength, corrosion resistance, and high-temperature performance. However, with the continuous improvement of equipment performance requirements, traditional titanium alloy ring rolled parts gradually expose the following technical bottlenecks: 1. Existing titanium alloys (such as Ti-6Al-4V) are prone to tissue degradation in high-temperature environments above 600 °C, resulting in a significant decrease in creep resistance and fatigue strength; 2. The traditional forging + ring rolling process has limited ability to regulate the microstructure of materials, and it is difficult to achieve the coordinated optimization of grain refinement and isotropy; 3. The introduction of externally added reinforcing phases (such as ceramic particles) often causes stress concentration due to interfacial reactions or uneven distribution, reducing the reliability of materials.

[0003] In response to the above technical bottlenecks, existing technologies mostly improve the tissue uniformity by optimizing rolling process parameters or using β forging, but none of them can break through the intrinsic performance limit of materials, and there are problems such as high energy consumption, long cycle, and low material utilization rate.

[0004] In view of this, the present invention is specifically proposed. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above-mentioned disadvantages of the existing technology and provide a high-strength and high-ductility titanium matrix composite ring and its preparation method and application.

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

[0007] In the first aspect, the present invention provides a preparation method of a high-strength and high-ductility titanium matrix composite ring. First, mix titanium alloy powder and reinforcing phase powder evenly, then obtain a ring blank according to the process flow of "melting → plasma rotating electrode atomization → degassing and sealing welding → hot isostatic pressing → ring rolling", and finally anneal the ring blank to obtain the target ring; wherein, the weight of the reinforcing phase powder is 0.1-1 wt% of the total weight of the mixed powder after being mixed evenly.

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

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

[0010] Step 2: Prepare a titanium-based composite rod: Place the mixed powder in a vacuum induction furnace and melt it multiple times in an inert gas atmosphere to obtain a titanium-based composite rod;

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

[0012] Step 4: Powder loading: Load the target section powder into a ring-shaped envelope and then perform degassing and sealing welding treatments;

[0013] Step 5: Prepare a ring blank: Perform hot isostatic pressing on the envelope filled with the target section powder after degassing and sealing welding treatments to obtain a ring blank;

[0014] Step 6: Multi-pass ring rolling: Heat and keep the ring blank warm and then perform multi-pass ring rolling to obtain a target ring blank; wherein, the heating temperature is 900 - 980 °C, and the heat preservation time is 120 - 180 min;

[0015] Step 7: Heat treatment: Perform heat treatment on the target ring blank to obtain a target ring part.

[0016] Further, low / medium / high temperature environment applicable and low / medium / high strength grade titanium alloy powders can be selected as the titanium alloy matrix powders, such as TC4 powder, TC11 powder, TC18 powder, Ti60 powder, etc., and nano-scale carbon black powder, pure silicon powder or micron-scale TiB2 powder can be selected as the reinforcing phase powders. Among them, 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 matrix powder is 53 - 106 μm, and the particle size of the reinforcing phase powder is 20 nm - 1 μm.

[0017] Among them, the titanium alloy powders are classified according to the application environment temperature as follows: Medium temperature environment applicable titanium alloy refers to the generally used temperature range of 350 - 500 °C, and high temperature environment applicable titanium alloy refers to the generally used temperature range of 500 - 650 °C; the titanium alloys are classified according to the strength grade as follows: Medium strength titanium alloy refers to its tensile strength of about 800 - 1000 MPa, high strength titanium alloy refers to its tensile strength of about 1000 - 1250 MPa, and ultra-high strength titanium alloy refers to its tensile strength higher than 1250 MPa.

[0018] Furthermore, 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 - 1.0 wt%, TiB2 powder 0.3 - 0.5 wt%, pure silicon powder 0.1 - 0.3 wt%.

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

[0020] First, perform 2 - 3 passes of ring rolling, with a single pass 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, perform 3 - 4 passes of ring rolling, with a single pass 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 treatment is 890 - 960 °C, the pressure is 130 - 200 MPa, and the holding time is 1 - 3 h.

[0023] Further, in step 4, the design parameters of the annular jacket are as follows:

[0024] The inner diameter of the annular jacket 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 ring part, and the thickness of the annular jacket is 3 - 8 mm.

[0025] Further, in step 4, degassing is carried out by heating degassing, and the relevant parameters are as follows: the vacuum degree ≤ 5×10 - 3 Pa, the heating temperature is 400 - 500 °C, and the holding time is 6 - 8 h.

[0026] Further, in step 3, the relevant parameters of the plasma rotating electrode atomization powder making process are as follows: the vacuum degree ≤ 1.1×10 -2 Pa, the voltage is 60 - 85 V, the current is 1700 ± 100 A, and the rotation speed is 28000 ± 500 r / min; the particle size range of the target section 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 relevant parameters of the melting are as follows: the vacuum degree ≤ 5×10 -3 Pa, the melting temperature is 1650 - 1850 °C, and the melting time is 25 - 35 min.

[0028] Further, in step 1, the mixing is carried out by mechanical mixing using a mixer in a vacuum environment, and the vacuum degree ≤ 1.1×10 -2Pa, the rotation speed is 120 - 150 r / min, and the mixing time is 30 - 35 h; when mixing the titanium alloy matrix powder and the reinforcing phase powder: first place the titanium alloy powder and half of the reinforcing phase powder in a mixer and mix evenly, then add the remaining reinforcing phase powder and continue to mix evenly. 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 °C, the holding time is 1 - 5 h, and the cooling method is water quenching or air cooling.

[0030] In the second aspect, the present invention also provides a high-strength and high-ductility titanium matrix composite ring prepared by the above-mentioned preparation method in part or in whole. The mechanical properties of the target ring are improved by 35% - 45% in terms of room temperature yield strength and 20% - 30% in terms of fracture toughness.

[0031] In addition, the present invention also provides an application of the above-mentioned preparation method in part or in whole in the preparation of titanium matrix composite rings for aviation structural parts under different service conditions.

[0032] Compared with the prior art, the technical solutions provided by the present invention have the following beneficial effects:

[0033] 1) The introduction of in-situ self-generated reinforcing phases in the titanium matrix composite can produce strong interfacial bonding with the titanium alloy matrix. This structure can effectively prevent crystal slip and intergranular slip, thus significantly improving the yield strength of the material. Moreover, due to the presence of the reinforcing phases and strong interfacial bonding, the titanium matrix composite can more effectively resist fatigue damage when subjected to external forces. In addition, the presence of the reinforcing phases can absorb and disperse external stresses, preventing the further propagation of internal cracks in the material, thereby improving the impact resistance of the material;

[0034] 2) Applying this preparation method to the near-net-shape powder metallurgy blanking process, the powder is not easily contaminated during the process, and the powder does not need to reach the molten state and then cool down, thus reducing the secondary segregation of elements. The microstructure is more uniform than that of the casting / forging process, and it can withstand lower temperatures and higher strain rates without cracking;

[0035] 3) The present invention uses "bulk mixing + vacuum induction melting to make rods + plasma rotating electrode atomization method" to replace the traditional laboratory small-batch ball milling method to prepare titanium matrix composite powder, which can introduce the reinforcing phase into the titanium matrix grains and distribute it evenly, and is suitable for industrial large-scale production to meet the actual industrial needs; by using the "powder metallurgy blanking + hot deformation" process to prepare titanium matrix composite rings, the dimensional accuracy of powder metallurgy forming and the high efficiency of special-shaped ring rolling can be used to reduce the processing period, improve the material utilization rate and the forming rate.

[0036] In summary, the present invention innovatively proposes a preparation method for a short-process, high-strength and high-plasticity titanium-based composite ring part with a "smelting-plasma rotating electrode atomization-hot isostatic pressing-ring rolling" four-in-one process: by mixing titanium alloy matrix powder and reinforcing phase powder, a composite bar is made by induction melting. After precision turning, the composite bar is used as a consumable electrode for the raw material of powder making by the plasma rotating electrode atomization method. The centrifugal force generated by the high-speed rotation (28000-32000 rpm) of the electrode refines the molten droplets, and combined with the rapid cooling of argon gas, spherical titanium-based composite powder with high sphericity is formed. The obtained titanium-based composite powder is filled into an annular sleeve and then degassed and welded. After completion, hot isostatic pressing is carried out for densification to make a blank. At the same time, combined with the ring rolling process, by establishing the matching relationship between the roll speed ratio (roll strain rate) and the deformation amount, the reinforcing phase is induced to be oriented along the grain boundary. Combining the thermomechanical treatment technology, gradient cooling is introduced during the rolling process to promote the simultaneous occurrence of dynamic recrystallization and β→α phase transformation, and finally a dual-mode structure of "equiaxed α + fibrous / granular reinforcement" is obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings herein are incorporated into and constitute a part of this specification, and together with the specification are used to explain the principles of the present invention.

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0039] Figure 1 It is a flow chart of the preparation method for the high-strength and high-plasticity titanium-based composite ring part provided by the present invention;

[0040] Figure 2 It is a manufacturing process flow chart of a high-strength and high-plasticity titanium-based composite ring part provided by the present invention;

[0041] Figure 3 It is a three-dimensional thermo-mechanical coupling finite element model diagram of the titanium-based composite process of the present invention;

[0042] Figure 4 It is a kinematic relationship diagram of each roll in the titanium-based composite ring process of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] Here, the exemplary embodiments will be described in detail. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. On the contrary, they are only examples consistent with some aspects of the present invention detailed in the appended claims.

[0044] The present invention uses low / mid / high temperature applicable and low / mid / high strength grade titanium alloys as matrix powders. By introducing reinforcing phase powders, combining powder metallurgy and hot deformation processes, and coordinating heat treatment systems to control the volume fractions of equiaxed α phase, lath α phase, and transformed β structure; leveraging the strong pinning effect of in-situ generated reinforcing phases and the hindrance effect of grain refinement on dislocations after recrystallization of some grains during ring rolling, the strength of the material is significantly improved without sacrificing too much of the elongation of the material; for high-strength near-β titanium alloys, the solution aging process can be further coordinated to control the proportion and morphology of phases to meet the different mechanical property requirements under different working service conditions of ring parts. Generally speaking, the present invention uses the above short process, high precision, less processing, and high utilization rate process means to produce large-sized, uniformly structured titanium matrix composite ring parts with excellent mechanical properties, thus effectively solving the problems of long production cycle and low mechanical properties of traditional forged ring parts.

[0045] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0046] See Figures 1 to 2 , the present invention provides a method for preparing a high-strength and ductile titanium matrix composite ring part. First, mix the titanium alloy powder and the reinforcing phase powder evenly, and then prepare a ring blank according to the process flow of "melting → plasma rotating electrode atomization → degassing and sealing welding → hot isostatic pressing → ring rolling", and finally anneal the ring blank to obtain the target ring part; wherein, the weight of the reinforcing phase powder is 0.1-1 wt% of the total weight of the mixed powder after being mixed evenly.

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

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

[0049] Step 2, preparing a titanium matrix composite bar: Place the mixed powder in a vacuum induction furnace and perform multiple meltings in an inert gas atmosphere to obtain a titanium matrix composite bar;

[0050] Step 3, powder making: Based on the titanium matrix composite bar, use the plasma rotating electrode atomization method to make titanium matrix composite powder, and obtain the target section powder for preparing the ring blank after screening;

[0051] Step 4, powder loading: Load the target section powder into a ring-shaped sleeve and perform degassing and sealing welding treatments;

[0052] Step 5, preparing a ring blank: Perform hot isostatic pressing on the sleeve filled with the target section powder after degassing and sealing welding treatments to obtain a ring blank;

[0053] Step 6, multi-pass ring rolling: After heating and insulating the annular blank, perform multi-pass ring rolling to obtain a target ring-rolled part; among them, the heating temperature is 900-980°C, and the insulation time is 120-180 min; multi-pass ring rolling adopts the titanium-based composite ring process, and the kinematic relationships of each rolling mill in this process are as Figure 4 shown.

[0054] Step 7, heat treatment: Perform heat treatment on the target ring-rolled part to obtain a target annular part.

[0055] Example 1

[0056] This example provides a method for preparing a high-strength and high-ductility titanium-based composite material annular part, including the following steps:

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

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

[0059] Powder mixing: Place the selected titanium alloy matrix powder and half of the reinforcing phase powder in a mixer and mix evenly, then add the other half of the reinforcing phase powder and continue to mix evenly. The protective gas is argon, the vacuum degree ≤ 1.1×10 -2 Pa, the rotation speed is 120 r / min, and the mixing time is 35 h;

[0060] Step 2, prepare a titanium-based composite bar: Place the evenly mixed mixed powder in a vacuum induction furnace and melt it in an atmosphere protected by high-purity argon; the vacuum degree of the melting chamber ≤ 5×10 -3 Pa, the melting temperature is 1670-1690°C, the melting time is 25 min, repeat melting 3 times, and process it to obtain a titanium-based composite bar after cooling to room temperature;

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

[0062] Step 4, powder loading: Load the powder of the target section into an annular jacket, and then perform heat degassing, impurity removal, and sealing welding treatments; the manufacturing material of the annular jacket is selected as 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 heat degassing process, the required vacuum degree is ≤5×10 -3 Pa, the heating temperature is 420 °C, and after holding for 7 h, perform five-pass sealing welding treatment;

[0063] Step 5, preparation of annular blank: Perform hot isostatic pressing densification sintering treatment on the jacket filled with the powder of the target section after degassing and sealing welding treatments to obtain a TC4-based annular blank. The temperature of the hot isostatic pressing treatment is 910 - 930 °C, the pressure is 135 ± 5 MPa, the holding time is 150 min, and the furnace cooling rate is 10 °C / min;

[0064] Step 6, multi-pass ring rolling: Heat and hold the TC4-based annular blank and then perform multi-pass ring rolling to obtain the target ring-rolled part; among them,

[0065] the heating temperature is 950 °C, the holding time is 150 min. After the heating and holding are completed, take out the TC4-based annular blank and perform the first-pass ring rolling to obtain an intermediate ring part, the rolling deformation amount is 10%, and the rolling strain rate is 0.05 s -1 ;

[0066] Due to the strong pinning effect of the titanium matrix composite reinforcement on the grain boundary, the ring rolling must be carried out in small amounts and multiple passes. After the first-pass ring rolling is completed, hold for 40 min to remove part of the residual stress, then take out the intermediate ring part and perform the second-pass ring rolling, the rolling deformation amount is 10%, and the rolling strain rate remains unchanged; perform the third-pass ring rolling under the same parameters;

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

[0068] Step 7, heat treatment: Perform homogenization annealing treatment on the target annular blank, the temperature is 750 °C, hold for 120 min, and the cooling method is air cooling;

[0069] Step 8, machining: Perform machining treatment on the target annular blank after annealing treatment, and finally obtain a TC4-based composite material annular part with specifications of φ100×φ50×20 mm.

[0070] Example 2

[0071] This embodiment provides a method for preparing a high-strength and high-plasticity titanium matrix composite ring, which includes the following steps:

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

[0073] Material selection: Select micron-sized α+β dual-phase TC11 titanium alloy as the titanium alloy matrix powder, with a particle size of 53-106 μm, and select nano-sized TiB2 powder as the reinforcing phase (precursor) powder, with a particle size of 40 nm and a purity of 99.9%; and the weight of the nano-sized TiB2 powder is 0.3-0.5 wt% of the total weight of the mixed powder after being mixed evenly;

[0074] Powder mixing: Place the selected titanium alloy matrix powder and half of the reinforcing phase powder in a mixer and mix evenly, then add the other half of the reinforcing phase powder and continue to mix evenly. The protective gas is argon, the vacuum degree ≤ 1.1×10 -2 Pa, the rotation speed is 130 r / min, and the mixing time is 32 h;

[0075] Step 2, preparing a titanium matrix composite rod: Place the evenly mixed powder in a vacuum induction furnace and melt it in a high-purity argon gas protection atmosphere; the vacuum degree of the melting chamber ≤ 5×10 -3 Pa, the melting temperature is 1710-1730 °C, the melting time is 35 min, repeat melting 2 times, and process it to obtain a titanium matrix composite rod after cooling to room temperature;

[0076] Step 3, powder making: Based on the titanium matrix composite rod, use the plasma rotating electrode atomization method, with a vacuum degree ≤ 1.1×10 -2 Pa, voltage 78 V, current 1750 A, rotation speed 30000 r / min to obtain titanium matrix composite powder. After screening, select the powder with a particle size range of 75-150 μm and a median diameter D50 of 110 μm in the laser particle size distribution for subsequent preparation of the ring blank. The powder composition should meet the requirements of GB / T 3620.1-2016, and the oxygen content in the powder element composition is 80 ppm and the nitrogen content is 21 ppm;

[0077] Step 4, powder loading: Load the target section powder into a ring-shaped sleeve and then perform heat degassing, impurity removal and sealing welding treatment; the material for making the ring-shaped sleeve is selected as 45 steel, the inner diameter of the sleeve is about 40 mm, the outer diameter of the sleeve is about 128 mm, the height of the sleeve is about 32 mm, and the wall thickness of the sleeve is about 4.5 mm; during the heat degassing process, the required vacuum degree ≤ 5×10 -3 Pa, the heating temperature is 400 °C, and after heat preservation for 8 h, perform five-pass sealing welding treatment;

[0078] Step 5: Prepare the ring blank: Subject the jacket filled with the target section powder after degassing and sealing welding to hot isostatic pressing densification sintering to obtain a TC11-based ring blank. The temperature of the hot isostatic pressing treatment is 950 ± 10°C, the pressure is 145 ± 5 MPa, the holding time is 180 min, and the furnace cooling rate is 10°C / min;

[0079] Step 6: Multi-pass ring rolling: Heat and hold the TC11-based ring blank and then perform multi-pass ring rolling to obtain the target ring-rolled part; among them,

[0080] The heating temperature is 980°C, the holding time is 150 min. After the heating and holding are completed, take out the TC11-based ring blank and perform the first-pass ring rolling to obtain an intermediate ring. The rolling deformation amount is 8%, and the rolling strain rate is 0.02 s -1 ;

[0081] Due to the strong pinning effect of the titanium matrix composite reinforcement on the grain boundary, the ring rolling must be carried out in small amounts and multiple times. After the first-pass ring rolling is completed, hold for 60 min to remove part of the residual stress. Then take out the intermediate ring and perform the second-pass ring rolling. The rolling deformation amount is 8%, and the rolling strain rate remains unchanged; perform the third-pass ring rolling under the same parameters;

[0082] The total rolling deformation amount of the first three passes is 24%. To avoid cracking, three more small-deformation ring rollings are required later. The holding time is 30 min, the deformation amount is 6%, and the strain rate is 0.03 s -1 , and the rolling deformation amount of the last three passes is 18%; the ring rolling process has a total of 6 passes, and the total deformation amount is 42%, and finally a target ring blank of φ118×φ35×26 mm is obtained;

[0083] Step 7: Heat treatment: Perform homogenization annealing treatment on the target ring blank, the temperature is 850°C, the holding time is 60 min, and the cooling method is air cooling;

[0084] Step 8: Machining: Perform machining treatment on the target ring blank after annealing treatment to finally obtain a TC11-based composite material ring with a specification of φ100×φ50×20 mm.

[0085] Example 3

[0086] This example provides a method for preparing a high-strength and high-ductility titanium matrix composite material ring, including the following steps:

[0087] Step 1: Material selection and mixing: Mix the selected titanium alloy matrix powder and the reinforcement phase powder to obtain a mixed powder, which can be realized by subdividing it into two steps:

[0088] Material selection: Select micron-sized near-β type TC18 titanium alloy as the titanium alloy matrix powder, with a particle size of 53 - 106 μm, and select micron-sized pure silicon powder as the reinforcement phase powder, with a particle size of 1 μm and a purity of 99.9%; and the weight of the micron-sized pure silicon powder is 0.1 - 0.3 wt% of the total weight of the mixed powder after mixing evenly.

[0089] Powder mixing: Place the selected titanium alloy matrix powder and half of the reinforcement phase powder in a mixer and mix evenly, then add the other half of the reinforcement phase powder and continue to mix evenly. The protective gas is argon, the vacuum degree ≤ 1.1×10 -2 Pa, the rotation speed is 140 r / min, and the mixing time is 31 h.

[0090] Step 2: Prepare the titanium matrix composite bar: Place the evenly mixed powder in a vacuum induction furnace and melt it in an atmosphere protected by high-purity argon; the vacuum degree of the melting chamber ≤ 5×10 -3 Pa, the melting temperature is 1720 ± 10 °C, the melting time is 35 min, repeat melting 3 times, and process to obtain the titanium matrix composite bar after cooling to room temperature.

[0091] Step 3: Powder making: Based on the titanium matrix composite bar, use the plasma rotating electrode atomization method, with a vacuum degree ≤ 1.1×10 -2 Pa, voltage 85 V, current 1650 A, rotation speed 31000 r / min to obtain the titanium matrix composite material powder. After screening, select the powder with a particle size range of 75 - 150 μm and a laser particle size distribution median diameter D50 of 110 μm for subsequent preparation of the ring blank. The powder composition should meet the requirements of GB / T 3620.1 - 2016, where the oxygen content in the powder element composition is 75 ppm and the nitrogen content is 15 ppm.

[0092] Step 4: Powder loading: Load the target section powder into a ring-shaped sleeve and then perform heating degassing, impurity removal, and sealing welding treatments; the material for making the ring-shaped sleeve is selected as 45 steel, the inner diameter of the sleeve is about 40 mm, the outer diameter of the sleeve is about 128 mm, the height of the sleeve is about 32 mm, and the wall thickness of the sleeve is about 4.5 mm; during the heating degassing process, the required vacuum degree ≤ 5×10 -3 Pa, the heating temperature is 420 °C, keep warm for 7 h and then perform five-pass sealing welding treatment.

[0093] Step 5: Prepare the ring blank: Perform hot isostatic pressing densification sintering treatment on the sleeve filled with the target section powder after degassing and sealing welding treatments to obtain the TC18-based ring blank. The temperature of the hot isostatic pressing treatment is 890 - 910 °C, the pressure is 140 ± 5 MPa, the holding time is 60 min, and the furnace cooling rate is 10 °C / min.

[0094] Step 6, multi-pass ring rolling: After heating and holding the TC18-based ring blank, perform multi-pass ring rolling to obtain the target ring-rolled part; among them,

[0095] The heating temperature is 900 °C, the holding time is 120 min. After the heating and holding are completed, take out the TC18-based ring blank and perform the first-pass ring rolling to obtain an intermediate ring part. The rolling deformation amount is 12%, and the rolling strain rate is 0.1 s -1 ;

[0096] Due to the strong pinning effect of the titanium matrix composite reinforcement on the grain boundary, the ring rolling must be carried out in small amounts and multiple times. After the first-pass ring rolling is completed, hold for 20 min to remove part of the residual stress. Then take out the intermediate ring part and perform the second-pass ring rolling. The rolling deformation amount is 24%, and the rolling strain rate remains unchanged;

[0097] The total rolling deformation amount of the first two passes is 24%. To avoid cracking, four more small-deformation ring rollings are required later. The holding time is 40 min, the deformation amount is 7%, and the strain rate is 0.05 s -1 , and the rolling deformation amount of the last four passes is 28%; The ring rolling process has a total of 6 passes, and the total deformation amount is 52%. Finally, a target ring blank of φ118×φ35×26 mm is obtained;

[0098] Step 7, heat treatment: Perform solution aging treatment on the target ring blank. The solution treatment system: 860 °C / 2 h / water cooling, the aging treatment system: 750 °C / 4 h / air cooling;

[0099] Step 8, machining: Perform machining on the target ring blank after annealing treatment to finally obtain a TC18-based composite material ring part with a specification of φ100×φ50×20 mm.

[0100] Example 4

[0101] This example provides a method for preparing a high-strength and high-ductility titanium matrix composite material ring part, including the following steps:

[0102] Step 1, material selection and mixing: Mix the selected titanium alloy matrix powder and the reinforcement powder to obtain a mixed powder, which can be realized in two steps:

[0103] Material selection: Select micron-scale near-α type Ti60 titanium alloy as the titanium alloy matrix powder, its particle size is 53 - 106 μm, select nano-scale TiB2 powder as the reinforcement powder, its particle size is 40 nm, and the purity is 99.9%; and the weight of the nano-scale TiB2 powder is 0.1 - 0.3 wt% of the total weight of the mixed powder after mixing evenly;

[0104] Powder mixing: Put the selected titanium alloy matrix powder and half of the reinforcing phase powder into a mixer and mix them evenly. Then add the other half of the reinforcing phase powder and continue to mix evenly. The protective gas is argon, the vacuum degree ≤ 1.1×10 -2 Pa, the rotation speed is 150 r / min, and the mixing time is 30 h;

[0105] Step 2: Prepare a titanium-based composite rod: Put the evenly mixed powder into a vacuum induction furnace and melt it in an atmosphere protected by high-purity argon; the vacuum degree of the melting chamber ≤ 5×10 -3 Pa, the melting temperature is 1800 ± 50 °C, the melting time is 25 min, repeat melting 3 times, and process it to obtain a titanium-based composite rod after cooling to room temperature;

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

[0107] Step 4: Powder loading: Put the target section powder into a ring-shaped sleeve and then perform heat degassing, impurity removal, and sealing welding treatments; the manufacturing material of the ring-shaped sleeve is selected as 45 steel, the inner diameter of the sleeve is about 40 mm, the outer diameter of the sleeve is about 128 mm, the height of the sleeve is about 32 mm, and the wall thickness of the sleeve is about 4.5 mm; during the heat degassing process, the required vacuum degree ≤ 5×10 -3 Pa, the heating temperature is 420 °C, keep it warm for 7 h and then perform five-pass sealing welding treatment;

[0108] Step 5: Prepare a ring blank: Perform hot isostatic pressing densification sintering treatment on the sleeve filled with the target section powder after degassing and sealing welding treatments to obtain a Ti60-based ring blank. The temperature of the hot isostatic pressing treatment is 940 - 960 °C, the pressure is 140 ± 5 MPa, the holding time is 180 min, and the furnace cooling rate is 10 °C / min;

[0109] Step 6: Multi-pass ring rolling: Heat and keep the Ti60-based ring blank warm and then perform multi-pass ring rolling to obtain the target ring-rolled part; among them,

[0110] the heating temperature is 950 °C, the holding time is 150 min. After heating and holding, take out the Ti60-based ring blank and perform the first-pass ring rolling to obtain an intermediate ring part, the rolling deformation amount is 10%, and the rolling strain rate is 0.05 s -1 ;

[0111] Due to the strong pinning effect of the reinforcement phase of the titanium matrix composite on the grain boundaries, the ring rolling must be carried out in small amounts and multiple times. After the first pass of ring rolling, it is kept warm for 40 min to remove some of the residual stress, and then the intermediate ring is taken out for the second pass of ring rolling. The rolling deformation is 10%, and the rolling strain rate remains unchanged; the third pass of ring rolling is carried out with the same parameters;

[0112] The total rolling deformation of the first three passes is 30%. To avoid cracking, three more ring rollings with small deformation amounts are needed later. The holding time is 40 min, the deformation amount is 7%, and the strain rate is 0.03 s -1 , and the rolling deformation 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 ring blank of φ120×φ36×28 mm is obtained;

[0113] Step 7, heat treatment: The target ring blank is subjected to homogenization annealing treatment at a temperature of 600 °C for 300 min, and the cooling method is air cooling;

[0114] Step 8, machining: The target ring blank after annealing treatment is machined, and finally a Ti60-based composite material ring with a specification of φ100×φ50×20 mm is obtained.

[0115] Relevant mechanical property experiments are carried out on the Ti-based composite material rings with different grades prepared in the above Examples 1-4. The experiments show that the room temperature tensile strength of the target ring is increased to 1450 MPa (35%-45% higher than that of traditional titanium alloys), the high temperature strength retention rate at 800 °C exceeds 75%, and at the same time the fracture toughness is increased by 20%-30%. In addition, as shown in Figure 3 , by establishing a "reinforcement phase distribution - process regulation - property mapping" model, the radial / axial mechanical property gradient of the target ring can be accurately regulated, so as to meet the dual requirements of "load-bearing - weight reduction" for components such as aero-engine casings.

[0116] In summary, the preparation method provided by the present invention innovates in aspects such as material design, preparation process, and forming technology: ① By using the process of "mixing - vacuum induction melting to make rods - plasma rotating electrode powder making", ceramic reinforcement phases are successfully introduced into the titanium alloy matrix. Due to the relatively fast cooling rate and small size of the reinforcement phases, titanium matrix composite powders with nanoscale reinforcement phases inside can be obtained; ② The in-situ self-reinforcement technology (such as TiBw / Ti system) is adopted to generate nanoscale TiB whiskers through the in-situ reaction of Ti - TiB2, realizing good interfacial compatibility between the reinforcement phase and the matrix and avoiding the interfacial pollution problem of traditional externally added reinforcements; ③ The combined preparation process of "powder metallurgy + ring rolling" is developed. By regulating the powder particle size distribution and sintering parameters, three-dimensional uniform dispersion of the reinforcement phases is ensured; ④ In the ring rolling forming stage, the small-variable multi-pass rolling process is used to promote the oriented arrangement of the reinforcement phases, and fine grain strengthening and the synergistic optimization of the reinforcement phase orientation are realized through dynamic recrystallization.

[0117] The entire preparation process is time-consuming, highly efficient, and has the great advantages of high precision and less machining, greatly improving the material utilization rate. It is applicable to industrial mass production and is conducive to quickly preparing high-performance titanium matrix composite ring parts. Specifically, through the deep coupling of "material - process - forming" as described above, the present invention compresses the traditional ring part production process to five steps, increases the material utilization rate from 42% to 80%, reduces the machining allowance by more than 60%, and significantly enhances the mechanical properties. The room temperature yield strength is increased by 40%, and the fracture toughness is increased by 25%. It has significant engineering application value.

[0118] The above are only specific implementation manners of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0119] It should be understood that the present invention is not limited to the content already described above and can be modified and changed without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A preparation method of a high-strength and high-plasticity titanium-based composite ring, characterized in that, First, mix the titanium alloy powder and the reinforcing phase powder evenly, and then prepare a ring blank according to the process flow of "melting → plasma rotating electrode atomization → degassing and sealing welding → hot isostatic pressing → ring rolling", and finally anneal the ring blank to obtain the target ring; wherein, the weight of the reinforcing phase powder is 0.1-1 wt% of the total weight of the mixed powder after being mixed evenly.

2. The preparation method of the high-strength and high-plasticity titanium matrix composite ring according to claim 1, wherein, The specific steps are as follows: Step 1, material selection and mixing: Mix the selected titanium alloy matrix powder and the reinforcing phase powder to obtain a mixed powder; Step 2, prepare a titanium matrix composite bar: Place the mixed powder in a vacuum induction furnace and carry out multiple meltings in an inert gas atmosphere to obtain a titanium matrix composite bar; Step 3, powder making: Based on the titanium matrix composite bar, use the plasma rotating electrode atomization method to obtain titanium matrix composite material powder, and obtain the target section powder for preparing the ring blank after screening; Step 4, powder loading: Load the target section powder into a ring-shaped jacket and then carry out degassing and sealing welding treatment; Step 5, prepare a ring blank: Carry out hot isostatic pressing treatment on the jacket filled with the target section powder after degassing and sealing welding treatment to obtain a ring blank; Step 6, multi-pass ring rolling: Heat and keep the ring blank warm and then carry out multi-pass ring rolling to obtain a target ring blank; wherein, the heating temperature is 900-980 °C, and the heat preservation time is 120-180 min; Step 7, heat treatment: Carry out heat treatment on the target ring blank to obtain a target ring; 3. The preparation method of the high-strength and high-plasticity titanium matrix composite ring according to claim 2, characterized in that, In Step 6, the multi-pass ring rolling is specifically: First, perform 2 to 3 passes of ring rolling. The single-pass deformation amount is 8% to 12%, the strain rate is 0.02 to 0.1 s -1 , the heat preservation time is 20 to 60 min, and the total deformation amount is 20% to 30%; Then perform ring rolling for 3 to 4 passes, with a single pass deformation of 5% to 10% and a strain rate of 0.02 to 0.05 s -1 , a holding time of 20 to 40 min, and a total deformation of 20% to 30%.

4. The preparation method of the high-strength and plastic titanium-based composite material ring according to claim 2, characterized in that, In Step 5, the temperature of the hot isostatic pressing treatment is 890-960 °C, the pressure is 130-150 MPa, and the heat preservation time is 1-3 h.

5. The preparation method of the high-strength and high-plasticity titanium matrix composite ring according to claim 2, characterized in that, In Step 4, The design parameters of the ring-shaped jacket are as follows: the inner diameter of the ring-shaped jacket 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 jacket is 3-8 mm; Degassing is carried out by heating degassing, and the relevant parameters are as follows: the vacuum degree ≤ 5×10 -3 Pa, the heating temperature is 400 - 500 °C, and the heat preservation time is 6 - 8 h.

6. The preparation method of the high-strength and plastic titanium matrix composite ring according to claim 2, characterized in that, In Step 3, the relevant parameters of the plasma rotating electrode atomization powder-making process are as follows: the vacuum degree ≤ 1.1×10 -2 Pa, the voltage is 60 - 85V, the current is 1700 ± 100A, and the rotation speed is 28000 ± 500 r / min.

7. The preparation method of the high-strength and plastic titanium-based composite material ring according to claim 2, characterized in that, In Step 2, the relevant parameters of the smelting are as follows: the vacuum degree ≤ 5×10 -3 Pa, the smelting temperature is 1650 - 1850 °C, and the smelting time is 25 - 35 min.

8. The preparation method of the high-strength and high-plasticity titanium matrix composite ring according to claim 2, characterized in that, In Step 1, the mixing is carried out by a mixer in a vacuum environment with a vacuum degree ≤ 1.1×10 -2 Pa, a rotation speed of 120 - 150 r / min, and a mixing time of 30 - 35 h.

9. A high-strength and high-ductility titanium matrix composite ring prepared by the preparation method according to any one of claims 1 to 8, characterized in that, The mechanical properties of the target ring are improved by 35%-45% compared with the room temperature yield strength, and the fracture toughness is increased by 20%-30%.

10. An application of the preparation method according to any one of claims 1-8 in the preparation of titanium matrix composite material rings for aviation structural parts under different service conditions.

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