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CN-122007295-A - Wide-width homogeneous high-toughness TC4ELI titanium alloy forging and high-precision preparation method thereof

CN122007295ACN 122007295 ACN122007295 ACN 122007295ACN-122007295-A

Abstract

The invention belongs to the technical field of titanium and titanium alloy processing, and relates to a high-precision preparation method of a wide-width homogeneous high-toughness TC4ELI titanium alloy forging. Selecting a finished cast ingot prepared by VAR smelting for at least three times, forging the finished cast ingot for 8-10 times to prepare a forging stock D, performing double heat treatment on the forging stock D to obtain a TC4ELI titanium alloy finished forging, and finally performing performance and flaw detection to obtain the TC4ELI titanium alloy finished forging meeting the standard. The invention forms a uniform and compact three-dimensional streamline through reversing upsetting, has sufficient equiaxial and small anisotropism, and applies advanced free forging technologies such as FM forging, blocking tongue forging and the like, so that on one hand, the initiation of surface cracks can be actively restrained, on the other hand, the metal can be more fully deformed in the length direction of the forging, and the traditional plate and tongue cutting process is omitted while the fiber flow direction is optimized, thereby greatly improving the material utilization rate, shortening the production period and reducing the comprehensive cost.

Inventors

  • QIAO ENLI
  • ZHU YINGGUANG
  • HU XIAONAN
  • GU ZHONGMING
  • LIU HULIN
  • YAN KANGQI
  • MA XUEFANG
  • Gao Fanglan
  • WU QIAN
  • ZHAO YINGHUI

Assignees

  • 新疆湘润新材料科技有限公司

Dates

Publication Date
20260512
Application Date
20260203

Claims (10)

  1. 1.A high-precision preparation method of a wide-width homogeneous high-toughness TC4ELI titanium alloy forging piece is characterized by selecting a finished product cast ingot with the specification of phi 760-phi 975mm obtained through at least three VAR smelting processes, forging the finished product cast ingot for 8-10 times to obtain a forging stock D, performing double heat treatment on the forging stock D to obtain a TC4ELI titanium alloy finished product forging piece, and finally performing performance and flaw detection on the TC4ELI titanium alloy finished product forging piece to obtain a TC4ELI titanium alloy finished product forging piece meeting the standard.
  2. 2. The high-precision preparation method of the wide-width homogeneous high-toughness TC4ELI titanium alloy forging piece is characterized by comprising the following steps of: Step 1, selecting a finished product cast ingot with the specification of phi 760-phi 975mm, which is prepared by VAR smelting for at least three times; Step 2, forging the finished cast ingot for 8-10 times to obtain a forging stock D; Step 3, performing dual heat treatment on the forging stock D, wherein the first heavy high-temperature annealing temperature is T β - (30-50) DEG C, the heat preservation is performed for 1-3 hours, the second heavy low-temperature annealing temperature is 700-800 ℃, and the heat preservation is performed for 1-3 hours, so that a TC4ELI titanium alloy finished forging is obtained; And 4, performing performance and flaw detection on the TC4ELI titanium alloy finished product forging to finish high-precision preparation of the target wide-width homogeneous high-toughness TC4ELI titanium alloy forging.
  3. 3. The high-precision preparation method of the wide-range homogeneous high-toughness TC4ELI titanium alloy forge piece is characterized by comprising the steps of in step 1, designing and using 0A-grade titanium sponge, aluminum beans, aluminum vanadium 65 alloy, ferrotitanium alloy and titanium dioxide according to the component proportion to obtain an alloy mixture, and pressing the alloy mixture into an electrode for three times to obtain a finished cast ingot.
  4. 4. The method for preparing the wide-width homogeneous high-toughness TC4ELI titanium alloy forging with high precision according to claim 2, wherein in the step 2, the 8-10 hot forging treatment comprises the following steps of, Heating the finished cast ingot to T β + (100-200) DEG C for forging to obtain a forging stock A, wherein the cogging forging comprises a forging operation of two upsetting and two drawing, and the ratio of the height to the diameter of the finished cast ingot during upsetting is 1.5-2.5; Intermediate forging, namely performing high-temperature forging by one fire and performing low-temperature forging by 5-7 fires; The high-temperature forging is performed in a temperature range of T β + (50-100) DEG C, and the heat preservation time is 180-300 min; The low-temperature forging is performed in a temperature range of T β - (30-50) DEG C, the heat preservation time is 360-480 min, and the low-temperature forging comprises reversing upsetting forging, FM forging and blocking tongue forging technology which are sequentially performed; And forging a fire finished product, namely drawing and deforming the blank obtained through intermediate forging at a temperature of T β - (30-50) DEG C, preserving the heat for 210-300 min, and straightening to obtain a forging blank D.
  5. 5. The high-precision preparation method of the wide-width homogeneous high-toughness TC4ELI titanium alloy forge piece, according to claim 4, is characterized in that the cogging forging specifically comprises the following steps: Preheating the finished cast ingot in a temperature range of 750-850 ℃, keeping the temperature for 90-150 min, heating the finished cast ingot to T β + (100-200) DEG C in 90-210 min, keeping the temperature for 180-300 min, and forging the cast ingot by two upsetting and two pulling-out blanks to obtain a forging blank A.
  6. 6. The high-precision preparation method of the wide-width homogeneous high-toughness TC4ELI titanium alloy forge piece, according to claim 4, is characterized in that the high-temperature forging of the intermediate forging is specifically as follows: Preheating a forging stock A obtained by cogging forging in a temperature range of 750-850 ℃, keeping the temperature for 90-150 min, heating the forging stock A to T β + (50-100) DEG C in 90-210 min, keeping the temperature for 180-300 min, then performing two upsetting and two drawing, wherein the initial forging temperature is more than or equal to 900 ℃, the final forging temperature is more than 850 ℃, and polishing the surface after forging to obtain a forging stock B.
  7. 7. The high-precision preparation method of the wide-width homogeneous high-toughness TC4ELI titanium alloy forge piece, according to claim 6, is characterized in that the low-temperature forging of the intermediate forging is specifically as follows: Preheating the forging stock B in a temperature range of 750-850 ℃, keeping the temperature for 90-150 min, heating the forging stock B to T β - (30-50) DEG C in 90-210 min, keeping the temperature for 360-480 min, then performing two upsetting and two drawing, wherein the initial forging temperature is more than or equal to 800 ℃, the final forging temperature is more than 750 ℃, and polishing the surface after forging to obtain the forging stock C.
  8. 8. The high-precision preparation method of the wide-width homogeneous high-toughness TC4ELI titanium alloy forge piece, according to claim 7, is characterized in that the finished forging specifically comprises: And heating the forging stock C obtained by intermediate forging to T β - (30-50) DEG C, keeping the temperature for 210-300 min, then carrying out an elongation process, wherein the initial forging temperature is more than or equal to 800 ℃ and the final forging temperature is more than 750 ℃, and straightening the forging stock C after forging to obtain a forging stock D.
  9. 9. The method for preparing the TC4ELI titanium alloy forged piece with high precision, which is wide and homogeneous and high-toughness according to claim 2, is characterized in that in the step 3, the forged piece D is straightened after double annealing is finished, and the same plate difference is controlled to be less than or equal to 5mm and the curvature is controlled to be less than or equal to 3mm/m, so that the TC4ELI titanium alloy forged piece is obtained.
  10. 10. The wide-width homogeneous high-toughness TC4ELI titanium alloy forging prepared by the preparation method according to any one of claims 1-9, which is characterized by longitudinal overall yield strength R p0.2 >810MPa, tensile strength R m >875MPa, elongation after fracture A 4D >13%, reduction of area Z >30%, transverse overall yield strength R p0.2 >800MPa, tensile strength R m >875MPa, elongation after fracture A 4D >13%, reduction of area Z >30% and fracture toughness K IC ＞77MPa·m 1/2 .

Description

Wide-width homogeneous high-toughness TC4ELI titanium alloy forging and high-precision preparation method thereof Technical Field The invention belongs to the technical field of titanium and titanium alloy processing, and relates to a high-precision preparation method of a wide-width homogeneous high-toughness TC4ELI titanium alloy forging. Background The TC4ELI titanium alloy is used as a typical low-clearance (particularly, the content of clearance elements such as O, N, H is controlled at a lower level) alpha+beta two-phase titanium alloy, and is an ideal material in the fields of aerospace critical bearing structures, deep sea equipment pressure-resistant shells, high-speed rail traffic bogies, high-end medical implants and the like due to the excellent specific strength, fracture toughness, corrosion resistance and good biocompatibility. With the development of high-end equipment to the large-scale, lightweight and high reliability, the specification and performance of TC4ELI titanium alloy forgings are more required, and development of wide forgings with large projection area and large thickness is needed. However, the preparation of the forgings faces serious technical challenges that the forming difficulty is extremely high, macroscopic defects such as insufficient filling, profile corner collapse, surface tearing and the like are extremely easy to occur in the free forging process of the wide forgings, the tissue performance is complex to control, the traditional free forging process is difficult to synchronously obtain uniform and fine equiaxed or bimodal tissues in the whole wide cross section, particularly in the central area, and risks such as coarse-grain and fine-grain bright bands of the central area exist, the process window is narrow, the alloy is extremely sensitive to forging temperature, the forging window of a narrow (alpha+beta) phase area causes the temperature fluctuation to easily cause the microstructure to be out of control, the plasticity, the toughness and the fatigue performance to be obviously scattered, the cracking tendency is increased, the internal stress state of the wide forgings is complex in the deformation process, extremely high requirements are put on the quality of original blanks and the setting of forging process parameters, and otherwise internal or surface cracking is easy to be initiated. At present, the conventional free forging process or rolling technology is difficult to break through the wide size limit and ensure that the forging has high uniformity, high toughness and stable medium strength level. In view of the foregoing, there is a need to develop a novel high-precision preparation method of a wide-width homogeneous high-toughness TC4ELI titanium alloy forging, which solves the above problems systematically, and further realizes stable preparation of a wide-width TC4ELI titanium alloy forging with high toughness and uniform structure. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a high-precision preparation method of a wide-width homogeneous high-toughness TC4ELI titanium alloy forging. In order to achieve the above purpose, the present invention provides the following technical solutions: on the one hand, the invention provides a high-precision preparation method of a wide-width homogeneous high-toughness TC4ELI titanium alloy forging, which comprises the steps of selecting a finished product cast ingot with the specification of phi 760-phi 975mm obtained through at least three times of VAR smelting, forging the finished product cast ingot for 8-10 times to obtain a forging stock D, performing double heat treatment on the forging stock D to obtain a TC4ELI titanium alloy finished product forging, and finally performing performance and flaw detection to obtain the TC4ELI titanium alloy finished product forging meeting the standard. Specifically, the high-precision preparation method specifically comprises the following steps: Step 1, selecting a finished product cast ingot with the specification of phi 760-phi 975mm, which is prepared by VAR smelting for at least three times; Step 2, forging the finished cast ingot for 8-10 times to obtain a forging stock D; Step 3, performing dual heat treatment on the forging stock D, wherein the first heavy high-temperature annealing temperature is T β - (30-50) DEG C, the heat preservation is performed for 1-3 hours, the second heavy low-temperature annealing temperature is 700-800 ℃ and the heat preservation time is 1-3 hours, and a TC4ELI titanium alloy finished forging is obtained; And 4, performing performance and flaw detection on the TC4ELI titanium alloy finished forging to finish high-precision preparation of the target wide-width homogeneous high-toughness TC4ELI titanium alloy forging. In the step 1, 0A grade sponge titanium, aluminum beans, aluminum vanadium 65 alloy, ferrotitanium alloy and titanium dioxide are used according to the component proporti