A Ti2AlNb / (α+β)Ti dual alloy disk and its preparation method

Abstract

The present invention provides a method for preparing a Ti2AlNb / (α+β)Ti dual alloy disk, comprising the following steps: designing a dual alloy disk forging and a forging preform; preparing a near-Ti2AlNb metal cladding transition zone and a near-(α+β)Ti metal cladding transition zone of the dual alloy disk; preparing a central metal cladding connection zone of the dual alloy disk; forging the dual alloy disk; and heat treating the dual alloy disk. The present application also provides a Ti2AlNb / (α+β)Ti dual alloy disk. The preparation method provided in the present application can achieve a continuous gradient transition of the composition and microstructure of the metallurgical bonding zone of the Ti2AlNb / (α+β)Ti dual alloy disk, which is beneficial for thermal stress relaxation during use and avoids load and stress concentration caused by fault-type connections. The present invention can be used to prepare aircraft engine compressor disks to meet tailoring performance requirements and weight reduction needs.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material processing, in particular to a Ti2AlNb / (α+β)Ti dual alloy disk and a preparation method thereof. Background Art

[0002] High thrust-to-weight ratio aircraft engines require components that deliver exceptional performance while also achieving maximum structural weight reduction. As a rotor component within the engine, the compressor disc's service conditions place significant demands on the disc's performance: the disc rim, connecting to the blades, operates at high temperatures and bears low loads, necessitating high creep and fracture toughness requirements; the disc core, operating at low temperatures and subject to significant centrifugal forces, places high demands on material strength, plasticity, and fatigue properties. These tailored performance requirements pose significant challenges to traditional disc manufacturing technologies.

[0003] At present, deformed high-temperature alloys (such as GH4169 alloy) are widely used as the material of high-pressure compressor discs in China. However, they have problems such as heavy weight and single performance, and have become increasingly difficult to adapt to the lightweight and efficient manufacturing requirements of engines. Therefore, the use of high-performance lightweight materials and high-efficiency tailoring structures to prepare dual-performance discs has become an urgent need in the development of compressor discs.

[0004] The lightweight intermetallic compound Ti2AlNb, with a maximum operating temperature exceeding 700°C, is a promising aerospace structural material. However, due to its low plasticity, the alloy does not meet the performance requirements of the disk core. Combining Ti2AlNb as the wheel rim material and a two-phase titanium alloy with an operating temperature of 350°C to 600°C as the disk core material to create a Ti2AlNb / (α+β)Ti dual-alloy disk can leverage the respective performance advantages of each alloy, potentially revolutionizing the structure and performance potential of disk components.

[0005] For dual-alloy disks, the dissimilar metal interface is the weakest link in the disk. Defect-free metallurgical bonding and continuous gradient transition in the connection area are key to disk development. Researchers have conducted extensive research on the fabrication of Ti2AlNb / (α+β)Ti dual-alloy disks and on microstructure control and performance enhancement in the dissimilar alloy connection area. However, these efforts have failed to address the technical challenges of achieving continuous gradient transition in the dissimilar alloy connection area, limiting the engineering applications of Ti2AlNb / (α+β)Ti dual-alloy disks. Researchers are constantly searching for new processes and methods for the fabrication of Ti2AlNb / (α+β)Ti dual-alloy disks. Summary of the Invention

[0006] The technical problem solved by the present invention is to provide a method for preparing a Ti2AlNb / (α+β)Ti dual alloy disk. The preparation method provided in this application ensures that the Ti2AlNb / (α+β)Ti dual alloy disk has no metallurgical defects such as shrinkage cavities and holes, and the composition fluctuation in the transition zone is small, and the organizational properties achieve a gradient transition.

[0007] In view of this, the present application provides a method for preparing a Ti2AlNb / (α+β)Ti dual alloy disk, comprising the following steps:

[0008] A) designing the forging dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk based on the structural dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk, and reversely designing the forging preform dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk based on a preset forging deformation, wherein the forging preform dimensions include the dimensions of the Ti2AlNb alloy outer ring blank, the dimensions of the (α+β)Ti alloy inner ring blank, and the dimensions of the interface transition zone;

[0009] B) preparing a nearly Ti2AlNb metal cladding transition zone on the inner circumference of the Ti2AlNb alloy outer ring blank, and preparing a nearly (α+β)Ti metal cladding transition zone on the outer circumference of the (α+β)Ti alloy inner ring blank;

[0010] C) placing the preform obtained in step B) on a substrate, and preparing a central metal cladding connection zone between the near Ti2AlNb metal cladding transition zone and the near (α+β)Ti metal cladding transition zone;

[0011] The substrate is used to achieve coaxial alignment of the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank;

[0012] D) removing the base plate from the preform obtained in step C) to obtain a forged preform of a dual alloy disk; preheating the forged preform of the dual alloy disk and then forging it according to a preset forging deformation to obtain a dual alloy disk forging;

[0013] E) heat treating the dual alloy disk forging and then machining it to obtain a Ti2AlNb / (α+β)Ti dual alloy disk;

[0014] The near-Ti2AlNb metal cladding transition zone, the near-(α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared from Ti2AlNb alloy powder and (α+β)Ti alloy powder, and the ratio of the Ti2AlNb alloy powder and the (α+β)Ti alloy powder achieves a gradient transition in the transition zone.

[0015] Preferably, the near-Ti2AlNb metal cladding transition zone is prepared from 65-85 wt% of Ti2AlNb alloy powder and 15-35 wt% of (α+β)Ti alloy powder.

[0016] Preferably, the near (α+β)Ti metal cladding transition zone is prepared from 15-35 wt% of Ti2AlNb alloy powder and 65-85 wt% of (α+β)Ti alloy powder.

[0017] Preferably, the central metal cladding connection zone is prepared from 40-60 wt% of Ti2AlNb alloy powder and 40-60 wt% of (α+β)Ti alloy powder.

[0018] Preferably, the near Ti2AlNb metal cladding transition zone, the near (α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared by laser / electronic powder feeding additive process.

[0019] Preferably, the forging preheating temperature is T f =T β -(15~30)℃,time t f =D max ×(0.6~0.8)min / mm; where T β is the phase transition point of (α+β)Ti alloy, D max It is the maximum cross-sectional thickness of the forged preform of the dual alloy disk; the preset forging deformation is 30-70%.

[0020] Preferably, the heat treatment adopts a double annealing method of high temperature annealing and low temperature annealing, and the high temperature annealing temperature T h =T f +(5-10)℃,time t h = 1h~8h, air cooling or wind cooling; the low temperature annealing temperature T l =500℃~560℃,time t h = 4h~16h, air cooling; where T f Preheat temperature for forging.

[0021] The present application also provides a Ti2AlNb / (α+β)Ti dual alloy disk, comprising a Ti2AlNb alloy outer ring blank, an (α+β)Ti alloy inner ring blank, and an interface transition zone composited between the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank, wherein the interface transition zone comprises a Ti2AlNb metal cladding transition zone near the end of the Ti2AlNb alloy outer ring blank, a central metal cladding connection zone, and a (α+β)Ti metal cladding transition zone near the end of the (α+β)Ti alloy inner ring blank;

[0022] The near-Ti2AlNb metal cladding transition zone, the near-(α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared from Ti2AlNb alloy powder and (α+β)Ti alloy powder, and the ratio of the Ti2AlNb alloy powder and the (α+β)Ti alloy powder achieves a gradient transition in the transition zone.

[0023] Preferably, the near-Ti2AlNb metal cladding transition zone is prepared from 65-85wt% of Ti2AlNb alloy powder and 15-35wt% of (α+β)Ti alloy powder; the near-(α+β)Ti metal cladding transition zone is prepared from 15-35wt% of Ti2AlNb alloy powder and 65-85wt% of (α+β)Ti alloy powder; and the central metal cladding connection zone is prepared from 40-60wt% of Ti2AlNb alloy powder and 40-60wt% of (α+β)Ti alloy powder.

[0024] Preferably, in the radial direction, the thickness ratio of the near Ti2AlNb metal cladding transition zone, the near (α+β)Ti metal cladding transition zone and the central metal cladding connection zone is (1±0.5):(1±0.5):(1±0.5).

[0025] The present application provides a method for preparing a Ti2AlNb / (α+β)Ti dual alloy disk, which comprises the following steps: firstly, designing the size of a Ti2AlNb / (α+β)Ti dual alloy disk forging preform and the size of an interface transition zone of the dual alloy disk; then, additively cladding a mixed powder of Ti2AlNb alloy and (α+β)Ti alloy in different proportions at different parts of the interface bonding zone to achieve metallurgical bonding of a multi-layer transition of the dual alloy disk; then, forging modification and heat treatment strengthening are performed on the dual alloy forging preform; and finally, the dual alloy disk is obtained after machining. In the process of preparing Ti2AlNb / (α+β)Ti dual alloy disk, the present application prepares a near Ti2AlNb metal cladding transition zone, a near (α+β)Ti metal cladding transition zone and a central metal cladding connection zone on the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank, respectively, thereby realizing a gradient transition connection between the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank, and further improving the connection reliability of the Ti2AlNb alloy outer ring blank and the (α+β)Ti) alloy inner ring blank through subsequent forging and heat treatment processes, avoiding stress concentration and failure fracture caused by discontinuous fluctuations in the composition and organizational properties of the interface bonding area, thereby solving the "weak connection" problem inherent in the dual alloy interface. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the outline structure and dimensions of the dual alloy disk provided in Example 1 of the present invention;

[0027] Figure 2 Schematic diagram of the structural dimensions and metallurgical bonding area position dimensions of the dual alloy disc forging provided in Example 1 of the present invention;

[0028] Figure 3 A schematic diagram of the structure and dimensions of a forging preform provided in Example 1 of the present invention;

[0029] Figure 4 A schematic diagram of the substrate structure and dimensions provided in Example 1 of the present invention;

[0030] Figure 5 This is a schematic diagram of substrate positioning provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0031] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0032] In response to the technical difficulties such as metallurgical defects in the interface bonding zone and the fault-like transition of composition and organization in the traditional process of preparing Ti2AlNb / (α+β)Ti dual alloy disks, the present application provides a method for preparing Ti2AlNb / (α+β)Ti dual alloy disks, which sequentially prepares a near Ti2AlNb metal cladding transition zone, a near (α+β)Ti metal cladding transition zone and a central metal cladding connection zone between the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank, and eliminates metallurgical defects such as shrinkage cavities / voids in the dual alloy metallurgical bonding zone through forging modification and heat treatment strengthening, thereby making the composition jump of the dissimilar metal interface bonding zone small and the organization performance gradient transition, solving the technical problem of "weak connection" of dissimilar alloys, and achieving high thrust ratio engine compressor disk tailoring performance and component weight reduction. Specifically, the embodiment of the present invention discloses a method for preparing Ti2AlNb / (α+β)Ti dual alloy disk, comprising the following steps:

[0033] A) designing the forging dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk based on the structural dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk, and reversely designing the forging preform dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk based on a preset forging deformation, wherein the forging preform dimensions include the dimensions of the Ti2AlNb alloy outer ring blank, the dimensions of the (α+β)Ti alloy inner ring blank, and the dimensions of the interface transition zone;

[0034] B) preparing a nearly Ti2AlNb metal cladding transition zone on the inner circumference of the Ti2AlNb alloy outer ring blank, and preparing a nearly (α+β)Ti metal cladding transition zone on the outer circumference of the (α+β)Ti alloy inner ring blank;

[0035] C) placing the preform obtained in step B) on a substrate, and preparing a central metal cladding connection zone between the near Ti2AlNb metal cladding transition zone and the near (α+β)Ti metal cladding transition zone;

[0036] The substrate is used to achieve coaxial alignment of the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank;

[0037] D) removing the base plate from the preform obtained in step C) to obtain a forged preform of a dual alloy disk; preheating the forged preform of the dual alloy disk and then forging it according to a preset forging deformation to obtain a dual alloy disk forging;

[0038] E) heat treating the dual alloy disk forging and then machining it to obtain a Ti2AlNb / (α+β)Ti dual alloy disk;

[0039] The near-Ti2AlNb metal cladding transition zone, the near-(α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared from Ti2AlNb alloy powder and (α+β)Ti alloy powder, and the ratio of the Ti2AlNb alloy powder and the (α+β)Ti alloy powder achieves a gradient transition in the interface transition zone.

[0040] In the preparation process of Ti2AlNb / (α+β)Ti dual alloy disk, the forging and forging preform are designed first, that is, the forging size of Ti2AlNb / (α+β)Ti dual alloy disk is designed according to the structural size of Ti2AlNb / (α+β)Ti dual alloy disk, and the forging preform size of Ti2AlNb / (α+β)Ti dual alloy disk is reversely designed according to the preset forging deformation amount. The forging preform size includes the Ti2AlNb alloy outer ring blank size, the (α+β)Ti alloy inner ring blank size and the interface transition zone size. In this application, (α+β)Ti is specifically a two-phase titanium alloy with an operating temperature between 350℃ and 600℃, including but not limited to TC2 alloy, TC4 alloy, TC4 alloy, TC6 alloy, TC11 alloy, and TC17 alloy; in a specific embodiment, the (α+β)Ti is TC11 alloy.

[0041] The present application then prepares a near Ti2AlNb metal cladding transition zone on the inner circumference of the Ti2AlNb alloy outer ring blank, and prepares a near (α+β)Ti metal cladding transition zone on the outer circumference of the (α+β)Ti alloy inner ring blank; before preparing the above-mentioned near Ti2AlNb metal cladding transition zone and the near (α+β)Ti metal cladding transition zone, the alloy powder used in the above-mentioned transition zone can be preferentially prepared; that is, the Ti2AlNb alloy powder and the (α+β)Ti alloy powder are evenly mixed according to different proportions to form powder formula A suitable for the near Ti2AlNb metal cladding transition zone, powder formula B suitable for the central metal cladding connection zone, and powder formula C suitable for the near (α+β)Ti metal cladding transition zone; in order to achieve a gradient of the dual alloy interface Transition, the formula A consists of 65-85wt% Ti2AlNb and 15-35wt% (α+β)Ti, the formula B consists of 40-60wt% Ti2AlNb and 40-60wt% (α+β)Ti, and the formula C consists of 65-85wt% Ti2AlNb and 15-35wt% (α+β)Ti; specifically, the formula A consists of 70-80wt% Ti2AlNb and 20-30wt% (α+β)Ti, the formula B consists of 45-55wt% Ti2AlNb and 45-55wt% (α+β)Ti, and the formula C consists of 70-80wt% Ti2AlNb and 20-30wt% (α+β)Ti.

[0042] In the present application, it is preferred to use a laser / electron beam powder feeding additive manufacturing process to prepare a near Ti2AlNb metal cladding transition zone and a near (α+β)Ti metal cladding transition zone respectively; specifically: using a laser / electron beam powder feeding additive manufacturing process to deposit a metal cladding layer of formula A on the inner circumference of the Ti2AlNb alloy outer ring blank, the size of the cladding layer should be slightly larger than the size of the near Ti2AlNb metal cladding transition zone; similarly, depositing a metal cladding layer of formula C on the outer circumference of the (α+β)Ti alloy inner ring blank, the size of the cladding layer should be slightly larger than the size of the near (α+β)Ti metal cladding transition zone; and then turning and finishing the cladding layer to the set size of the transition zone. In the present application, the laser / electron beam powder feeding additive manufacturing process is a manufacturing process well known to those skilled in the art, and this application does not impose any special restrictions on its specific implementation process, and it can be carried out in a manner well known to those skilled in the art.

[0043] The present application then prepares a central metal cladding connection area; prior to this, a substrate is first prepared, and the substrate is selected from Ti2AlNb alloy or (α+β)Ti alloy, which is used to achieve coaxial alignment of the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank; the specific shape of the substrate can be designed in a manner familiar to those skilled in the art. In the present application, the substrate is a substrate with two raised ring platforms, wherein the inner edge of the outer raised ring platform is tightly fitted with the outer circumference of the Ti2AlNb alloy outer ring blank to achieve fixation of the Ti2AlNb alloy outer ring blank, and the inner raised ring platform is located between the near Ti2AlNb metal cladding transition zone and the near (α+β)Ti metal cladding transition zone.

[0044] This application then places the above-mentioned preform on a substrate, and then prepares a central metal cladding connection area between the near Ti2AlNb metal cladding transition area and the near (α+β)Ti metal cladding transition area; the preparation of the central metal cladding connection area also adopts a laser / electron beam powder feeding additive manufacturing process, specifically: the laser / electron beam powder feeding additive manufacturing process is used to stack the metal cladding layer of formula B layer by layer in the central metal cladding connection area, after the cladding stacking is completed, the substrate is turned away, and the upper and lower surfaces are finish-machined to obtain a Ti2AlNb / (α+β)Ti dual alloy forging preform.

[0045] The present invention then preheats the Ti2AlNb / (α+β)Ti dual alloy forging preform and forges it according to a preset forging deformation, thereby obtaining a dual alloy disc forging; the forging preheating temperature is T f =T β -(15~30)℃,time t f =D max ×(0.6~0.8)min / mm; where T β is the phase transition point of (α+β)Ti alloy, D max The maximum cross-sectional thickness of the forged preform of the dual alloy disk; the preset forging deformation is 30-70%. The specific implementation of the forging is carried out in a manner well known to those skilled in the art and is not particularly limited in this application.

[0046] According to the present invention, the dual alloy disc forging is finally subjected to heat treatment, wherein the heat treatment is specifically a double annealing of high temperature annealing and low temperature annealing, wherein the temperature of the high temperature annealing is T h =T f +(5-10)℃,time t h = 1h~8h, air cooling or wind cooling, specific, t h =3h~6h; the low temperature annealing temperature T l =500℃~560℃,time t h=4h~16h, air cooling, specific, t h =6h~10h; where T f The forging preheating temperature and high-temperature annealing temperature are defined in the upper portion of the titanium alloy (α+β) phase region, allowing the titanium alloy matrix to obtain a dual-state structure with a good balance between strength and plasticity. Selecting a high-temperature annealing temperature slightly higher than the forging temperature allows the dual-state structure to have a fine secondary α strengthening phase, thereby improving the strength of the disc core. Furthermore, the forging and high-temperature annealing temperatures are located in the Ti2AlNb alloy (α2+B2+O) three-phase region, allowing the Ti2AlNb alloy matrix to obtain a structure with excellent overall performance.

[0047] The present application also provides a Ti2AlNb / (α+β)Ti dual alloy disk, comprising a Ti2AlNb alloy outer ring blank, an (α+β)Ti alloy inner ring blank, and an interface transition zone composited between the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank, wherein the interface transition zone comprises a Ti2AlNb metal cladding transition zone near the end of the Ti2AlNb alloy outer ring blank, a central metal cladding connection zone, and a (α+β)Ti metal cladding transition zone near the end of the (α+β)Ti alloy inner ring blank;

[0048] The near-Ti2AlNb metal cladding transition zone, the near-(α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared from Ti2AlNb alloy powder and (α+β)Ti alloy powder, and the ratio of the Ti2AlNb alloy powder and the (α+β)Ti alloy powder achieves a gradient transition in the interface transition zone.

[0049] In the present application, in the radial direction, the thickness ratio of the near Ti2AlNb metal cladding transition zone, the near (α+β)Ti metal cladding transition zone and the central metal cladding connection zone is (1±0.5):(1±0.5):(1±0.5).

[0050] The preparation method of the Ti2AlNb / (α+β)Ti dual alloy disk provided in the present application optimizes the dual alloy interface fault transition of the original process into a continuous transition by designing the dual alloy interface bonding area into a multi-layer gradient transition form. On the one hand, it can effectively reduce the interface thermal stress caused by the inconsistent linear expansion coefficient of the dual alloy, and on the other hand, it is beneficial to the load transfer at the interface bonding point and avoids stress concentration. The dual alloy forging preform with the layered gradient transition interface is subjected to forging deformation. Firstly, the residual stress caused by the additive cladding in the interface bonding area can be eliminated, and metallurgical defects such as shrinkage cavities can be closed. Secondly, the columnar crystal cast structure obtained by the additive cladding can be changed into an equiaxed forging structure, thereby improving the performance level of the interface bonding area. Thirdly, the forging deformation can be carried out. Deformation promotes the fusion of components in the interface bonding zone and introduces lattice defects such as dislocations, which can provide a channel for the diffusion of elements in the interface bonding zone in the subsequent heat treatment process, which is beneficial to improving the continuity of the composition transition in the interface bonding zone; furthermore, the forging deformation temperature and the high-temperature annealing temperature are located in the upper part of the titanium alloy (α+β)Ti phase zone, which can enable the titanium alloy matrix to obtain a dual-state structure with good strength and plasticity matching, and selecting a high-temperature annealing temperature slightly higher than the forging temperature can make the dual-state structure have a fine secondary α strengthening phase, thereby improving the strength level of the disk core. At the same time, the above-mentioned forging and high-temperature annealing temperatures are located in the Ti2AlNb alloy (α2+B2+O) three-phase zone, and the Ti2AlNb alloy matrix can obtain a structure with excellent comprehensive performance.

[0051] In order to further understand the present invention, the Ti2AlNb / (α+β)Ti dual alloy disk and its preparation method provided by the present invention are described in detail below in conjunction with the embodiments. The protection scope of the present invention is not limited by the following embodiments.

[0052] Example 1 Φ360mm×30mm (connection interface reference position Φ240mm) Ti2AlNb / TC11 dual alloy disk (structure size as Figure 1 The preparation method comprises the following steps:

[0053] (1) Design of forgings and forging preforms: Design the structural dimensions of the Ti2AlNb / TC11 dual alloy forgings based on the structural dimensions of the dual alloy disc ( Figure 2 As shown, ) and determine the size and location of the dual alloy metallurgical bonding area The deformation is preset to 50%, and the forging preform structure is reversely designed. The preform structure includes the structure size of the Ti2AlNb alloy outer ring blank ( Figure 3 As shown, ), TC11 alloy cylindrical billet structure dimensions Interface transition zone structural dimensions The interface transition zone is divided from the outside to the inside into the near Ti2AlNb transition zone Central connection area and near TC11 transition zone

[0054] (2) Powder preparation: Powder formula A suitable for the near Ti2AlNb transition zone was prepared, with the Ti2AlNb alloy powder content being 75wt% and the TC11 alloy powder content being 25wt%; Powder formula B suitable for the central connection zone was prepared, with the Ti2AlNb alloy powder content being 50wt% and the TC11 alloy powder content being 50wt%; Powder formula C suitable for the near TC11 transition zone was prepared, with the Ti2AlNb alloy powder content being 25wt% and the TC11 alloy powder content being 75wt%;

[0055] (3) Dual alloy transition zone cladding: The laser powder feeding additive process is used to deposit the metal cladding layer of formula A on the inner circumference of the Ti2AlNb alloy outer ring blank. The inner diameter of the cladding layer is controlled within The height exceeds the upper and lower end surfaces of the Ti2AlNb alloy outer ring blank by 5mm; similarly, a metal cladding layer of formula C is deposited on the outer circumference of the TC11 alloy cylindrical blank, and the outer diameter of the cladding layer is controlled at The height exceeds the upper and lower end surfaces of the TC11 alloy outer ring blank by 5mm; then the cladding layer is turned and finished to Figure 3 The set size in;

[0056] (4) Substrate design and processing: Ti2AlNb alloy is selected for design and processing. Figure 4 The substrate shown is provided with a positioning boss to achieve coaxial alignment of the Ti2AlNb alloy outer ring blank and the TC11 alloy cylindrical blank;

[0057] (5) Dual alloy additive cladding connection: The Ti2AlNb alloy outer ring blank with the cladding zone prepared in step (3) and the TC11 alloy cylindrical blank are placed on the substrate prepared in step (4) through clearance fit to achieve coaxial alignment; a metal cladding layer of formula B is deposited layer by layer in the central connection area using a laser powder feeding additive manufacturing process; after the cladding deposition is completed, the substrate is removed by turning, and the positioning boss position removed by turning is flipped up and down to be stacked, and finally the upper and lower surfaces are refined to form a Ti2AlNb / TC11 dual alloy forging preform;

[0058] (6) Dual alloy disc forging: Preheat the dual alloy forging preform to T f =T β -20℃(T β is 1005℃), forging preheating time t f = 60min, after the heat preservation is completed, the furnace is taken out and forged according to the 50% deformation amount preset in step (1), and the following is obtained: Figure 2 The dual alloy disc forging shown;

[0059] (7) Heat treatment of double alloy disc forgings: Double annealing heat treatment is performed on the double alloy disc forgings. The high temperature annealing temperature is T h =T β -10℃(T β is 1005℃), time t h =4h, air cooling; low temperature annealing temperature T l =530℃, time t h =8h, air cooling.

[0060] (8) Double alloy disc forging processing: turning method is used Figure 1 Dual alloy forgings are machined into duplex discs.

[0061] The above embodiments are only intended to help understand the method and core concept of the present invention. It should be noted that, without departing from the principles of the present invention, a number of improvements and modifications may be made to the present invention by those skilled in the art, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0062] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a Ti2AlNb / (α+β)Ti dual alloy disk, comprising the following steps: A) designing the forging dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk based on the structural dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk, and reversely designing the forging preform dimensions of the Ti2AlNb / (α+β)Ti dual alloy disk based on a preset forging deformation, wherein the forging preform dimensions include the dimensions of the Ti2AlNb alloy outer ring blank, the dimensions of the (α+β)Ti alloy inner ring blank, and the dimensions of the interface transition zone; B) preparing a nearly Ti2AlNb metal cladding transition zone on the inner circumference of the Ti2AlNb alloy outer ring blank, and preparing a nearly (α+β)Ti metal cladding transition zone on the outer circumference of the (α+β)Ti alloy inner ring blank; C) placing the preform obtained in step B) on a substrate, and preparing a central metal cladding connection zone between the near Ti2AlNb metal cladding transition zone and the near (α+β)Ti metal cladding transition zone; The substrate is used to achieve coaxial alignment of the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank; D) removing the base plate from the preform obtained in step C) to obtain a forged preform of a dual alloy disk; preheating the forged preform of the dual alloy disk and then forging it according to a preset forging deformation to obtain a dual alloy disk forging; E) heat treating the dual alloy disk forging and then machining it to obtain a Ti2AlNb / (α+β)Ti dual alloy disk; The near-Ti2AlNb metal cladding transition zone, the near-(α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared from Ti2AlNb alloy powder and (α+β)Ti alloy powder, and the ratio of the Ti2AlNb alloy powder and the (α+β)Ti alloy powder achieves a gradient transition in the transition zone.

2. The preparation method according to claim 1, characterized in that The near-Ti2AlNb metal cladding transition zone is prepared from 65-85wt% of Ti2AlNb alloy powder and 15-35wt% of (α+β)Ti alloy powder.

3. The preparation method according to claim 1, characterized in that The near (α+β)Ti metal cladding transition zone is prepared from 15-35wt% of Ti2AlNb alloy powder and 65-85wt% of (α+β)Ti alloy powder.

4. The preparation method according to claim 1, characterized in that The central metal cladding connection zone is prepared from 40-60 wt% of Ti2AlNb alloy powder and 40-60 wt% of (α+β)Ti alloy powder.

5. The preparation method according to claim 1, characterized in that The near Ti2AlNb metal cladding transition zone, the near (α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared by laser / electronic powder feeding additive process.

6. The preparation method according to claim 1, characterized in that The forging preheating temperature is T f =T β -(15~30)℃,time t f =D max ×(0.6~0.8)min / mm; where T β is the phase transition point of (α+β)Ti alloy, D max It is the maximum cross-sectional thickness of the forged preform of the dual alloy disk; the preset forging deformation is 30-70%.

7. The preparation method according to claim 1 or 6, characterized in that The heat treatment adopts a double annealing method of high temperature annealing and low temperature annealing, and the high temperature annealing temperature T h =T f +(5-10)℃,time t h = 1h~8h, air cooling or wind cooling; the low temperature annealing temperature T l =500℃~560℃,time t h = 4h~16h, air cooling; where T f Preheat temperature for forging.

8. A Ti2AlNb / (α+β)Ti dual alloy disk, comprising a Ti2AlNb alloy outer ring blank, an (α+β)Ti alloy inner ring blank, and an interface transition zone composited between the Ti2AlNb alloy outer ring blank and the (α+β)Ti alloy inner ring blank, the interface transition zone comprising a Ti2AlNb metal cladding transition zone near an end of the Ti2AlNb alloy outer ring blank, a central metal cladding connecting zone, and a (α+β)Ti metal cladding transition zone near an end of the (α+β)Ti alloy inner ring blank; The near-Ti2AlNb metal cladding transition zone, the near-(α+β)Ti metal cladding transition zone and the central metal cladding connection zone are all prepared from Ti2AlNb alloy powder and (α+β)Ti alloy powder, and the ratio of the Ti2AlNb alloy powder and the (α+β)Ti alloy powder achieves a gradient transition in the transition zone.

9. The Ti2AlNb / (α+β)Ti dual alloy disk according to claim 8, characterized in that The near-Ti2AlNb metal cladding transition zone is prepared from 65-85wt% of Ti2AlNb alloy powder and 15-35wt% of (α+β)Ti alloy powder; the near-(α+β)Ti metal cladding transition zone is prepared from 15-35wt% of Ti2AlNb alloy powder and 65-85wt% of (α+β)Ti alloy powder; the central metal cladding connection zone is prepared from 40-60wt% of Ti2AlNb alloy powder and 40-60wt% of (α+β)Ti alloy powder.

10. The Ti2AlNb / (α+β)Ti dual alloy disk according to claim 8, characterized in that In the radial direction, the thickness ratio of the near Ti2AlNb metal cladding transition zone, the near (α+β)Ti metal cladding transition zone and the central metal cladding connection zone is (1±0.5):(1±0.5):(1±0.5).

Images