Manufacturing method of anti-knock plate of hydraulic wrench

Abstract

The invention discloses a manufacturing method of an anti-knock plate of a hydraulic wrench. The manufacturing method comprises the following steps: SI, smelting an alloy raw material to obtain an as-cast alloy plate blank; s2, the as-cast titanium alloy plate blank is subjected to high-temperature cogging treatment; s3, in the beta-phase region, the as-cast titanium alloy plate is forged, and the forging speed and the deformation amount are controlled; s4, constant-temperature heating is conducted, the titanium alloy plate is subjected to solution treatment, and a more uniform beta solid solution is formed on the plate; s5, the titanium alloy plate is subjected to water cooling or air cooling, the cooling rate is controlled, and a cogging-state plate with high anti-knock performance is obtained; and S6, aging treatment is conducted on the two-phase region of the titanium alloy plate, and the required high-anti-explosion-performance plate is formed. S7, the materials are cooled to the normal temperature in a furnace cooling or air cooling mode; the plasticity and the impact toughness of the titanium alloy plate are improved, the ductility of the plate in the RD direction and the TD direction is kept at a good level, and the anti-explosion capacity in the ND direction is greatly improved.

Description

Technical Field

[0001] The present invention specifically relates to the technical field of plate manufacturing, and in particular to a method for manufacturing an explosion-resistant plate for a hydraulic wrench. Background Art

[0002] Hydraulic wrenches are hydraulic wrench tools primarily used for setting and outputting torque and are widely used across various industrial sectors. To ensure quality, they are often made from titanium alloy sheets. This quality also places stringent requirements on the strength, toughness, structural stability, and impact resistance of titanium alloys.

[0003] Conventional titanium alloy sheet manufacturing processes typically include smelting, forging, and heat treatment, but require minimal explosion-proof performance. Consequently, hydraulic wrenches exhibit relatively weak explosion-proof performance. To further enhance this performance, a manufacturing method is proposed that enhances the explosion-proof properties of titanium alloy sheet materials. Summary of the Invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a method for manufacturing an explosion-resistant plate for a hydraulic wrench.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for manufacturing an explosion-resistant plate for a hydraulic wrench comprises the following steps:

[0007] SI: The alloy raw materials are melted to obtain the cast alloy slab;

[0008] S2: subjecting the as-cast titanium alloy slab to a high-temperature cogging treatment;

[0009] S3: Forging the as-cast titanium alloy plate in the β phase region, controlling the forging rate and deformation to forge large lamellar β grains, with the resulting plate thickness ≥ 60 mm;

[0010] S4: Constant temperature heating to perform solid solution treatment on the titanium alloy plate, so that the plate forms a more uniform β solid solution;

[0011] S5: Cooling the titanium alloy plate with water or air, controlling the cooling rate, and obtaining a green sheet with high explosion resistance;

[0012] S6: Performing aging treatment in the two-phase region of the titanium alloy plate to form the required high explosion-resistant plate;

[0013] S7: Select furnace cooling or air cooling to cool the material to room temperature.

[0014] Furthermore, in S1, the thickness of the cast alloy slab is between 180 mm and 220 mm.

[0015] On the basis of the above scheme, in S2, the titanium alloy material is heated to 30-50° C. above the phase transition point and heated at a constant temperature for 240-360 minutes, so that larger β grains are formed inside the material.

[0016] As a further solution of the present invention, in S3, a small amount and multiple forging method is adopted, the forging speed is 30s / time, and the single feed amount is between 80-120mm.

[0017] Furthermore, in S3, the single deformation amount needs to be controlled within 15%-25%, and the total deformation amount needs to be controlled within 60%-70% to ensure uniform deformation of the plate.

[0018] On the basis of the above scheme, in S4, the solution treatment needs to be carried out in the β phase region, that is, 30-50°C above the phase transformation point, and the solution treatment time is 60-120 minutes.

[0019] As a further solution of the present invention, in S5, the plate temperature is made to reach 35°C below the phase transition point, that is, the plate temperature is less than 960°C, and then continues to be water-cooled or air-cooled to 650-800°C.

[0020] Furthermore, in S6, during the aging treatment, the plate is kept at a constant temperature of 650-800° C. for 60-120 minutes.

[0021] Based on the above scheme, in S7, the cooling time is 60-120 minutes.

[0022] The beneficial effects of the present invention are:

[0023] The method described in this patent only performs heat treatment on the material in the β phase region, and then performs heat treatment to accurately control the microstructural evolution of the plate, which greatly reduces the workload caused by the original two heat treatments in the β phase region and the two-phase region.

[0024] The titanium alloy plate obtained by this method has significantly improved elongation in the TD and RD directions, but poor elongation in the ND direction. The overall mechanical properties of the material are not significantly different from those of the homogenized plate. However, when the explosive impact load is loaded along the ND direction, the explosion resistance of the titanium alloy plate is significantly improved.

[0025] This patent makes full use of the Burgers orientation relationship. Through small amounts of multiple forging and high-temperature solution treatment in the β phase region, a strong {001}β or {111}β deformation wire texture in the ND direction is regulated in the β phase region. In the subsequent aging treatment in the α phase region, BCC is fully enabled to select variants to the corresponding HCP according to the Burgers orientation relationship, and a large amount of spherical primary α phase is precipitated at the same time, ensuring the fracture ductility and impact toughness of the material. Fine lamellar secondary α phase is precipitated during the furnace cooling process, further improving the plasticity and impact toughness of the titanium alloy plate, so that the ductility of the plate in the RD and TD directions remains at a good level, and the explosion resistance in the ND direction is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a metallographic image of a random portion on the intersection surface of TD and ND in Example 1;

[0027] Figure 2 This is a metallographic image of a random portion on the intersection surface of TD and ND in Example 2;

[0028] Figure 3 This is a metallographic image of a random portion on the intersection surface of TD and ND in Example 3;

[0029] Figure 4 The IPF / / Z0 image and the HCP grains in the sample in Example 3 are <0001> Orientation diagram. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0031] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this patent and are not to be construed as limiting this patent.

[0032] In the description of this patent, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," "connected," and "set" should be understood in a broad sense. For example, they can refer to fixed connection or set, detachable connection or set, or integral connection or set. Those skilled in the art will understand the specific meanings of the above terms in this patent based on the specific circumstances.

[0033] Example 1

[0034] Reference Figure 1A method for manufacturing an explosion-resistant plate for a hydraulic wrench comprises the following steps:

[0035] SI: The alloy raw materials are melted to obtain the cast alloy slab;

[0036] A metal powder is obtained by uniformly mixing 6.2 wt.% aluminum, 4.0 wt.% vanadium, and 0.2 wt.% iron, with the remainder being titanium. The powder is pre-pressed into small pieces and introduced into an argon atmosphere. A plasma arc is used as a high-temperature heat source to rapidly melt the metal powder or pre-pressed pieces introduced into a smelting zone, forming a stable small molten pool. The molten metal is then dripped by gravity into a water-cooled copper mold of predetermined size below, where it rapidly solidifies, thereby forming an ingot with a dense structure and minimal impurities. The thickness of the as-cast alloy slab ranges from 180 mm to 220 mm.

[0037] S2: The as-cast titanium alloy slab is subjected to a high-temperature cogging treatment, wherein the titanium alloy material is heated to 30-50°C above the phase transition point and heated at a constant temperature for 240-360 minutes, so that large β grains are formed inside the material, and a strong {001}β or {111}β deformation wire texture is obtained in the ND direction;

[0038] Specifically, a TC4 ingot containing a small amount of iron, with a length and width of 1000mm and a thickness of 200mm, was heated to 35°C above the phase transition point, that is, 1030°C, and heated at a constant temperature for 10 minutes to ensure that the ingot was heated evenly. It was then subjected to high-temperature heat treatment and heated at a constant temperature for 240-360 minutes.

[0039] S3: In the β phase region, the cast titanium alloy plate is forged, and the forging rate and deformation are controlled. In the regulation of the forging deformation, the dynamic recrystallization of the β grains should be taken into account to promote the acquisition of a strong {001}β or {111}β deformation wire texture in the ND direction, while refining the β grains to prevent the β grains from being too coarse and causing the α phase segregation. Therefore, a small amount and multiple forging method is required;

[0040] The forging rate should not be too fast, as it is not conducive to the dynamic recrystallization of the material and easily forms a distorted structure. The forging rate should not be too slow either, as it will result in excessive heat exposure time, which will lead to excessive growth of β grains and segregation of α precipitation. A moderate forging speed, i.e. 30s / time, is more appropriate.

[0041] The single feed amount is between 80-120mm, the single deformation amount needs to be controlled at 15%-25%, and the total deformation amount needs to be controlled at 60%-70% to ensure uniform deformation of the plate, so that large lamellar β grains are forged, and the resulting plate thickness is ≥60mm;

[0042] Specifically, the ingot is subjected to high-temperature stress forging in the β phase region, with a single feed of 100 mm and a forging cycle every 30 seconds. The total deformation of the plate forging is 60%. The first round of deformation is 25%, that is, the plate thickness becomes 150 mm, the second round of deformation is 20%, that is, the plate thickness becomes 120 mm, the third round of deformation is 20%, that is, the plate thickness becomes 100 mm, and the fourth round of deformation is 25%, that is, the plate thickness becomes 80 mm. A total of four rounds of forging are performed, with 10 strokes per round.

[0043] S4: Constant temperature heating, solution treatment of the titanium alloy plate. The solution treatment needs to be carried out in the β phase region, 30-50℃ above the phase transformation point, that is, the plate temperature is maintained at 1030℃. The solution time should not be too long, which will weaken the strong {001}β or {111}β deformation wire texture in the ND direction. The solution time should not be too short, otherwise it will lead to uneven distribution of material structure. The most suitable solution time is 120min, so that the plate forms a more uniform β solid solution.

[0044] S5: Cool the titanium alloy plate with water or air until the plate temperature reaches 35°C below the phase transition point, i.e., the plate temperature is less than 960°C, so that the β grains inhibit the phase transition diffusion process of the structure, making it difficult to transform into the equilibrium structure in time, thereby retaining a specific metastable structure or morphology, which is convenient for the result of variant selection to meet the expectation of controlling the strong {001}β or {111}β deformation filament texture in the ND direction in the composite Burgers orientation relationship;

[0045] Control the cooling rate and the cooling time is 60-120 minutes, followed by water cooling or air cooling to 650-800℃ to ensure that the β grain size in the TC4 plate does not change much, and obtain the open-blank plate with high explosion resistance;

[0046] S6: Aging treatment is performed in the two-phase region of the titanium alloy plate. The aging treatment time should not be too long, which may cause excessive precipitation of the α phase and form a needle-like structure. It should not be too short, which may lead to insufficient variant selection and poor overall material performance.

[0047] During the aging treatment, the plate is kept at a constant temperature of 650-800℃ for 60-120min, that is, the plate is subjected to heat insulation heat treatment, and the temperature of the plate is maintained at 800℃ for 120min to ensure that the α phase can precipitate and spheroidize in the plate. Then the furnace is cooled to room temperature to obtain a titanium alloy plate with a thickness of about 80mm, forming the required high explosion-resistant performance plate;

[0048] S7: Choose furnace cooling or air cooling to cool the material to room temperature. Rapid cooling will cause defects in the material, making the material high in strength but poor in plasticity and toughness. At the same time, reducing the cooling rate will make it easier to precipitate fine lamellar secondary α phase, making the titanium alloy plate more plastic and tough, and better overall performance. The cooling time is 60-120 minutes.

[0049] Example 2

[0050] Reference Figure 2

[0051] SI: 6.0wt.% aluminum, 4.0wt.% vanadium, 0.4wt.% copper, and the balance titanium are mixed uniformly to obtain metal powder. The metal powder is sent into an argon environment and then filled into a rigid mold of a predetermined size. High-pressure pressing is performed at room temperature to obtain a compact with a certain strength and shape. The compact is then sintered at a high temperature to form a metallurgical bond between the powder particles to obtain a TC4 titanium alloy ingot containing copper.

[0052] S2: A TC4 titanium alloy ingot with a size of 900 mm × 900 mm × 220 mm and containing a small amount of copper is heated to a temperature 45°C higher than its phase transition point, i.e., 1040°C. The ingot is kept at this temperature for 10 minutes to ensure uniform heating of the entire ingot, facilitating high-temperature thermal deformation treatment.

[0053] S3: Using a die forging hydraulic press, the ingot was subjected to high-temperature stress forging in the β phase region, with a single feed of 90mm and a forging rhythm of one stroke every 30 seconds. A total of five rounds, each with 10 strokes, resulted in a cumulative deformation of approximately 70%. Specifically, the first round saw a deformation of approximately 25%, reducing the thickness from 180mm to 165mm; the second round saw a deformation of approximately 21%, reducing the thickness to 130mm; the third round saw a deformation of approximately 19%, reducing the thickness to 105mm; the fourth round saw a deformation of approximately 19%, reducing the thickness to 85mm; and the fifth round saw a deformation of approximately 17%, resulting in a titanium alloy plate with a thickness of 70mm.

[0054] S4: The temperature is maintained at 1040°C and the plate is solution treated for 1 hour.

[0055] S5: Use air cooling to quickly cool the plate to 650-800℃;

[0056] S6: The plate is subjected to thermal aging treatment, maintaining the temperature of the plate at 750°C for 90 minutes to ensure that the α phase can precipitate and spheroidize in the plate. The furnace is then cooled to room temperature to obtain a titanium alloy plate with a thickness of about 70 mm.

[0057] S7: After cooling for 60-120 minutes, a titanium alloy plate is obtained.

[0058] Example 3

[0059] Reference Figure 3

[0060] S1: 6.2 wt.% aluminum, 4.0 wt.% vanadium, and the balance titanium are mixed uniformly to obtain metal powder, which is pre-pressed into small pieces. A titanium alloy electrode is melted by arc heating in a vacuum (or inert atmosphere), and the melted pieces are dripped dropwise into a water-cooled copper crucible to solidify into an ingot, thereby forming a TC4 titanium alloy ingot;

[0061] S2: Place a TC4 titanium alloy ingot with a size of 1200mm×1200mm×180mm in a high temperature environment at 1035℃ (about 40℃ higher than the β transition point) and heat it for 15 minutes to ensure that all parts of the ingot are heated evenly. After the heat preservation is completed, the β phase region is immediately subjected to heat treatment;

[0062] S3: The ingot is subjected to high-temperature stress forging in the β phase region. During the forging process, a single feed of 120 mm is used and a forging is performed every 30 seconds. The entire forging process is carried out in four rounds, with 10 forgings in each round, and the cumulative total deformation is about 60%. The specific deformation path is as follows: the first round deformation is about 25%, reducing the thickness of the plate from the original 180 mm to 135 mm; the second round continues to deform by about 22%, and the thickness is further reduced to 105 mm; the third round deformation is about 19%, and the thickness is reduced to 85 mm; the fourth round final deformation is about 17%, bringing the thickness to 70 mm;

[0063] S4: The temperature is maintained at 1040°C and the plate is solution treated for 1 hour.

[0064] S5: The plate is cooled by water cooling + air cooling. First, the plate is quickly cooled to 900℃ by water cooling to ensure that the β grain size in the TC4 plate does not change much. Then, it is air cooled to 650-800℃ to ensure the orderly selection of variants and the orderly precipitation and spheroidization of the primary α phase.

[0065] S6: The forged plate undergoes a heat treatment at 800°C for 120 minutes to promote the precipitation of the α phase and achieve spheroidization. After the heat treatment, the plate is cooled to room temperature using air cooling, resulting in a titanium alloy plate approximately 70 mm thick.

[0066] S7: After cooling for 60-120 minutes, a titanium alloy plate is obtained.

[0067] refer to Figure 4

[0068] A sample coordinate system was established, with the TD direction as the X direction, the ND direction as the Y direction, and the RD direction as the Z direction. A tensile machine was used to test the mechanical properties of the three samples of Examples 1, 2, and 3 in the RD, TD, and ND directions. The statistical results are shown in the following table:

[0069]

[0070] In the sample of Example 3, a large-area EBSD stitching was performed on a random location on the intersection of TD and ND to obtain an IPF / / Z0 image ( Figure 4 Left) and the HCP grains in the sample <0001> Orientation diagram ( Figure 4 right polar figure).

[0071] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for manufacturing an explosion-resistant plate for a hydraulic wrench, characterized in that: The following steps are involved: SI: The alloy raw materials are melted to obtain the cast alloy slab; S2: subjecting the as-cast titanium alloy slab to a high-temperature cogging treatment; S3: Forging the as-cast titanium alloy plate in the β phase region, controlling the forging rate and deformation to forge large lamellar β grains, with the resulting plate thickness ≥ 60 mm; S4: Constant temperature heating to perform solid solution treatment on the titanium alloy plate, so that the plate forms a more uniform β solid solution; S5: Cooling the titanium alloy plate with water or air, controlling the cooling rate, and obtaining a green sheet with high explosion resistance; S6: Performing aging treatment in the two-phase region of the titanium alloy plate to form the required high explosion-resistant plate; S7: Select furnace cooling or air cooling to cool the material to room temperature.

2. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In the above-mentioned S1, the thickness of the cast alloy slab is between 180 mm and 220 mm.

3. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In S2, the titanium alloy material is heated to 30-50° C. above the phase transition point and heated at a constant temperature for 240-360 minutes, so that large β grains are formed inside the material.

4. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In S3, a small amount and multiple forging method is adopted, the forging speed is 30s / time, and the single feed amount is between 80-120mm.

5. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 4, characterized in that: In the above-mentioned S3, the single deformation amount needs to be controlled within 15%-25%, and the total deformation amount needs to be controlled within 60%-70% to ensure uniform deformation of the plate.

6. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In the above-mentioned S4, the solution treatment needs to be carried out in the β phase region, that is, 30-50° C. above the phase transformation point, and the solution treatment time is 60-120 min.

7. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In the above-mentioned S5, the plate temperature is made to be 35°C below the phase transition point, that is, the plate temperature is less than 960°C, and then the plate temperature is further water-cooled or air-cooled to 650-800°C.

8. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In the above-mentioned S6, during the aging treatment, the plate is kept at a constant temperature of 650-800° C. for 60-120 minutes.

9. The method for manufacturing a hydraulic wrench explosion-resistant plate according to claim 1, characterized in that: In the step S7, the cooling time is 60-120 min.

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