Preparation method of composite solid-phase welding process test piece

Abstract

The invention relates to a preparation method of a composite solid-phase welding process test piece, which specifically comprises the following steps: step 1, firstly processing the welding surfaces of a titanium alloy test piece I and a titanium alloy test piece II into planes, and putting the two titanium alloy test pieces to be connected into a diffusion welding furnace to complete the preparation of a diffusion welding head; 2, the diffusion welding head prepared in the step 1 is machined to be in the size of a simulation part, linear friction welding is completed on linear friction welding equipment and a titanium alloy test block, and preparation of the diffusion welding-friction welding head is completed; the linear friction welding seam in the step and the diffusion welding seam in the step 1 are arranged in a T shape. And 3, processing the composite solid-phase welding test block into a composite solid-phase process test piece according to the design drawing. Effective fatigue test simulation of the hollow blade blisk subjected to diffusion welding and linear friction composite welding can be achieved, the feasibility of the diffusion welding and linear friction composite welding scheme is verified, the development and production requirements of products are met, and wide application prospects are achieved.

Description

Technical Field

[0001] The invention belongs to the field of welding technology, and in particular relates to a method for preparing a composite solid phase welding process test piece, and in particular relates to solid phase welding of an integral blade disk, which is used for manufacturing integral blade disk parts of an aero-engine. Background Art

[0002] Diffusion welding and friction welding are both solid-phase connection methods. The solid-phase connection method does not require the addition of flux during the welding process, and the welded joint is formed by directly connecting the metals to be welded. The principle of diffusion welding is that under the action of high temperature and pressure, the metal atoms in the interface diffuse with each other, and symbiotic grains are formed at the welding interface, which eventually connects the metal into a whole. The principle of friction welding is that the metal in the weld section reaches a plastic state under the action of friction, and the metal in the weld section recrystallizes, which eventually connects the metal into a whole. Both technologies can be used in the manufacture of aircraft engine parts. Diffusion welding is mainly used for the connection of fixed parts such as support plates, and friction welding is mainly used for the connection of rotating parts. At present, single welding technology has developed very maturely:

[0003] A Chinese patent (publication number: CN101367156A, publication date: February 18, 2009) discloses a linear friction welding method, including the following steps: setting the amplitude of the two welds to a constant amplitude, the vibration frequency increases from a lower frequency to a higher frequency at the beginning of the friction; then a constant frequency and constant amplitude friction stage, at which the vibration frequency and amplitude are constant; in the final stage of the friction, the amplitude gradually decreases, and when the amplitude gradually decreases to 0 to make the two welds return to the center, the top forging pressure is applied to complete the welding; during the entire welding process, the friction pressure is constant. Due to the larger amplitude and lower frequency in the initial stage of friction, the friction interface can be effectively mechanically cleaned and preheated; in the middle and late stages of friction, the amplitude gradually decreases to make the high temperature range of the joint wider and more uniform, and the deformed metal can be fully recovered and recrystallized, eliminating the residual stress of the welded joint and improving the quality of the joint.

[0004] Chinese patent (publication number: CN104551380A, publication date: April 29, 2015) CN201410811818.1 provides an integral blade disk and a manufacturing method thereof, comprising: (1) arranging and fixing all blades along the circumferential direction of a disk-shaped member; (2) linearly friction welding all blades and the disk-shaped member along the circumferential direction of the disk-shaped member; and simultaneously applying a top forging force along the axial direction of the disk-shaped member to keep the blades in contact with the disk-shaped member; (3) when the contact surface between the blade and the disk-shaped member is heated to the metal plastic deformation temperature, increasing the top forging force along the axial direction of the disk-shaped member so that the blade and the disk-shaped member are fixedly connected together to obtain a preform of the integral blade disk; and (4) post-processing the preform of step (3) to obtain an integral blade disk. When welding the blades to the blade disk in the manufacturing method of the present invention, since the blades and the blade disk perform high-speed reciprocating motion in the circumferential direction, when the welding is terminated, no matter where the blades stay, the relative position accuracy between the blades will not be affected, the requirements for equipment and process are greatly reduced, and the product yield is improved.

[0005] A Chinese patent (publication number: CN203509338U, publication date: April 2, 2014) discloses a new type of welding technology, specifically friction welding. The infrared preheating friction welding welding system includes a box body, a friction welding tool is arranged in the box body, and a heating plate, on which a heating wire is arranged according to the contour of the contact end face of the weldment; the heating plate is movably connected to the box body. The heating plate is connected to the box body through a rotating mechanism. The box body is provided with an openable door, and the friction welding tool is arranged on the inner side of the door. A glass window is provided on the door for easy observation of the working status. The rotating mechanism is connected to a power mechanism and driven by the power mechanism, and the power mechanism is connected to a control system. Then the action of the heating plate is controlled. After adding the heating wire, the weldment can be heated by the heating wire, and the heat generated by the heating wire and the heat generated by friction are organically combined, so that the contact end face of the weldment quickly reaches or approaches a molten state, which solves the problems of impurities, cold slag, slow welding speed and poor forming effect when welding is performed solely by heat generated by friction.

[0006] With the development of aviation technology, reasonable weight reduction is the development trend of engines, and material and structure are also the two key points of weight reduction. Hollow blades made of titanium alloy can effectively achieve the purpose of weight reduction. Then, for the manufacture of integral blades with hollow blade structure, the connection between the hollow blade and the disc body cannot be achieved by any single diffusion welding or linear friction welding mentioned above. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a method for preparing a composite solid phase welding process test piece, which solves the problem that traditional single solid phase welding methods including diffusion welding and friction welding cannot complete the connection between the blades and the disk body of the hollow fan blade integral disk, thereby making the structure of the integral blade disk parts lightweight and improving the specific strength and specific stiffness of the integral blade disk parts.

[0008] A method for preparing a composite solid phase welding process test piece specifically comprises the following steps:

[0009] Step 1: First, the welding surfaces of the two titanium alloy test pieces to be connected, namely, titanium alloy test piece I and titanium alloy test piece II, are processed into flat surfaces, and then the two titanium alloy test pieces are placed in a diffusion welding furnace to complete the preparation of the diffusion welding joint;

[0010] Step 2: Process the diffusion welding joint prepared in step 1 to the size of the simulated part, complete linear friction welding with the titanium alloy test block on a linear friction welding device, and complete the preparation of the diffusion welding-friction welding joint;

[0011] Step 3: Process the composite solid phase welding test block into a composite solid phase process test piece according to the design drawing.

[0012] The titanium alloy test piece I and the titanium alloy test piece II are hollow sheet-like titanium alloys, and the titanium alloy test block is a solid titanium alloy block.

[0013] The flatness in step 1 reaches 0.02 mm.

[0014] In the preparation of the diffusion welding joint in step 1, the diffusion welding furnace is heated to 800° C.-900° C., a pressure of 2 MPa-5 MPa is applied, and the furnace is taken out after keeping the temperature for 2-3 hours.

[0015] The welding parameters of the linear friction welding in step 2 are: pressure 60MPa-100MPa, frequency 30Hz-60Hz, amplitude 2mm-3mm.

[0016] The specific method of processing the diffusion welding joint to the size of the simulated part in step 2 is:

[0017] First, the surface where the diffusion weld is located is taken as the symmetry plane, and material is evenly removed on both sides of the diffusion welding joint; the surface on the diffusion welding joint that is perpendicular to the diffusion weld is used as the welding surface of the linear friction welding, and the processing is stopped when the length and width of the welding surface of the linear friction welding are the same as those of the titanium alloy test block, so that the welding surface of the diffusion welding joint is the same size as the welding surface of the titanium alloy test block.

[0018] The linear friction weld in step 2 is arranged in a T-shape with the diffusion weld in step 1.

[0019] The composite solid phase process test piece in step 3 is divided into two parts: a vibration part and a clamping part. The titanium alloy test piece I and the titanium alloy test piece II are the vibration part, and the titanium alloy test block is the fixed part. First, the linear friction weld is used as the boundary to complete the processing of the clamping part, and the processing size range is: height 55mm-57mm, width 49.9mm-50.1mm, thickness 4.5mm-5.5mm; then the diffusion weld is used as the center plane to complete the processing of the vibration part, and the processing size range is: height 69mm-71mm, width 29mm-31mm, thickness 25mm-27mm; the clamping part and the vibration part are transitioned by a circular arc.

[0020] The beneficial effects of the present invention are:

[0021] The present invention provides a method for preparing a composite solid phase welding process test piece, which can realize effective fatigue test simulation for a hollow blade integral blade disk that is compositely welded by diffusion welding and linear friction welding, verifies the feasibility of the diffusion welding and linear friction composite welding schemes, and has high parts manufacturing repetitive accuracy. It solves the manufacturing problem of the hollow blade integral blade disk that cannot be completed by the traditional single solid phase welding method, greatly improves the manufacturing accuracy of integral blade disk parts, improves the production efficiency and manufacturing qualification rate of integral blade disk parts, can meet the research and production needs of products, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of a diffusion welding joint in Example 1 of the present invention;

[0023] Figure 2 Schematic diagram of a diffusion welding-friction welding joint in Example 1 of the present invention;

[0024] Figure 3 Schematic diagram of a composite solid phase welding process test piece in Example 1 of the present invention (wherein Figure (a) is a front view and Figure (b) is a side view);

[0025] in,

[0026] 1-titanium alloy test piece I, 2-titanium alloy test piece II, 3-titanium alloy test block, 4-diffusion weld, 5-linear friction weld. DETAILED DESCRIPTION

[0027] In order to better explain the present invention and facilitate understanding, the technical solutions and effects of the present invention are described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0028] Example 1

[0029] This embodiment provides a method for preparing a composite solid phase welding process test piece, which specifically includes the following steps:

[0030] Step 1: First, the welding surfaces of the two titanium alloy test pieces to be connected, namely, titanium alloy test piece I1 and titanium alloy test piece II 2, are processed into planes with a flatness of 0.02 mm. Titanium alloy test piece I1 and titanium alloy test piece II 2 are placed in a diffusion welding furnace, heated to about 900°C, and a pressure of 2 MPa is applied. After keeping the temperature for 2 hours, the furnace is taken out to complete the preparation of the diffusion welding joint. Figure 1 shown.

[0031] The titanium alloy test piece I1 and the titanium alloy test piece II2 are hollow sheet-like titanium alloys to simulate the structure of a hollow blade, and the welds are located on the thickness side of the titanium alloy test piece I1 and the titanium alloy test piece II2.

[0032] Step 2: Process the diffusion welding joint prepared in step 1 to the size of the simulated part, specifically: first, take the surface where the diffusion weld is located as the symmetry plane, and evenly remove material on both sides of the diffusion welding joint formed by the titanium alloy test piece I1 and the titanium alloy test piece II 2; use the surface of the diffusion welding joint that is perpendicular to the diffusion weld as the welding surface of the linear friction welding, and stop processing when the length and width of the welding surface of the linear friction welding are the same as those of the titanium alloy test piece 3, so that the welding surface of the diffusion welding joint has the same size as the welding surface of the titanium alloy test piece 3. Then, perform linear friction welding on the assembly of test piece 1 and test piece 2 and test piece 3 on the linear friction welding equipment to complete the preparation of the diffusion welding-friction welding joint. Figure 2 shown.

[0033] Among them, the welding parameters are: pressure 100MPa, frequency 30Hz, amplitude 3mm.

[0034] The titanium alloy test block 3 is a solid titanium alloy block to simulate the disk structure of the integral blade disk.

[0035] The diffusion welding-friction welding joint has two welding processes, diffusion welding and friction welding. The linear friction weld 5 in this step and the diffusion weld 4 in step 1 are arranged in a T shape.

[0036] Step 3: Process the composite solid phase welding test block into a composite solid phase process test piece according to the design drawing:

[0037] The process test piece includes a vibration part and a clamping part, of which the titanium alloy test piece I1 and the titanium alloy test piece II2 are the vibration part, and the titanium alloy test piece 3 is the clamping part. First, the linear friction weld 5 is used as the boundary to complete the processing of the clamping part, and the size is 56mm in height × 50mm in width × 5mm in thickness. Then, the diffusion weld 4 is used as the center plane to complete the processing of the vibration part of the process test piece, and the size is 70mm in height × 30mm in width × 26mm in thickness. The clamping part and the vibration part are transitioned by an arc to ensure that the linear friction weld 5 is located at the intersection of the arc and the vibration part, such as Figure 3 shown.

[0038] Result analysis: The fatigue test piece prepared by the above method can simulate the welding structure of the integral blade disk with hollow blade structure for fatigue testing, and can be used for mechanical testing of the welded joint of the integral blade disk with hollow blade, meeting the use requirements of parts development. The method of the present invention has a good simulation effect for the fatigue test of the composite solid phase connection joint of the integral blade disk with hollow blade, meeting the use requirements of rapid verification of key technologies.

[0039] Example 2

[0040] This embodiment provides a method for preparing a composite solid phase welding process test piece, which specifically includes the following steps:

[0041] Step 1: First, the welding surfaces of the two titanium alloy test pieces to be connected, namely, titanium alloy test piece I1 and titanium alloy test piece II 2, are processed into a flat surface with a flatness of 0.02 mm. The titanium alloy test piece I1 and the titanium alloy test piece II 2 are placed in a diffusion welding furnace, heated to about 900°C, and a pressure of 5 MPa is applied. After keeping the temperature for 3 hours, the furnace is taken out to complete the preparation of the diffusion welding joint.

[0042] The titanium alloy test piece I1 and the titanium alloy test piece II2 are hollow sheet-like titanium alloys to simulate the structure of a hollow blade, and the welds are located on the thickness side of the titanium alloy test piece I1 and the titanium alloy test piece II2.

[0043] Step 2: Process the diffusion welding joint prepared in step 1 to the size of the simulated part, specifically: first, take the surface where the diffusion weld is located as the symmetry plane, and evenly remove material on both sides of the diffusion welding joint formed by the titanium alloy test piece I1 and the titanium alloy test piece II 2; use the surface of the diffusion welding joint that is perpendicular to the diffusion weld as the welding surface of the linear friction welding, and stop processing when the length and width of the welding surface of the linear friction welding are the same as those of the titanium alloy test piece 3, so that the welding surface of the diffusion welding joint has the same size as the welding surface of the titanium alloy test piece 3. Then, perform linear friction welding on the assembly of test piece 1 and test piece 2 and test piece 3 on the linear friction welding equipment to complete the preparation of the diffusion welding-friction welding joint. Figure 2 shown.

[0044] Among them, the welding parameters are: pressure 80MPa, frequency 50Hz, amplitude 2.5mm.

[0045] The titanium alloy test block 3 is a solid titanium alloy block to simulate the disk structure of the integral blade disk.

[0046] The diffusion welding-friction welding joint has two welding processes, diffusion welding and friction welding. The linear friction weld in this step and the diffusion weld in step 1 are arranged in a T shape.

[0047] Step 3: Process the composite solid phase welding test block into a composite solid phase process test piece according to the design drawing:

[0048] The process test piece includes a vibration part and a clamping part, of which the titanium alloy test piece I1 and the titanium alloy test piece II2 are the vibration part, and the titanium alloy test piece 3 is the clamping part. First, the clamping part is processed with the linear friction weld as the boundary, and the size is 70mm×30mm×26mm. Then, the vibration part of the process test piece is processed with the diffusion weld as the center plane, and the size is 50mm×56mm×5mm. The clamping part and the vibration part are transitioned by an arc to ensure that the linear friction weld is located at the intersection of the arc and the vibration part.

[0049] Result analysis: The fatigue test piece prepared by the above method can simulate the welding structure of the integral blade disk with hollow blade structure for fatigue testing, and can be used for mechanical testing of the welded joint of the integral blade disk with hollow blade, meeting the use requirements of parts development. The method of the present invention has a good simulation effect for the fatigue test of the composite solid phase connection joint of the integral blade disk with hollow blade, meeting the use requirements of rapid verification of key technologies.

Claims

1. A method for preparing a composite solid phase welding process test piece, characterized in that: The specific steps include: Step 1: First, the welding surfaces of the two titanium alloy test pieces to be connected, namely, titanium alloy test piece I and titanium alloy test piece II, are processed into flat surfaces, and then the two titanium alloy test pieces are placed in a diffusion welding furnace to complete the preparation of the diffusion welding joint; Step 2: Process the diffusion welding joint prepared in step 1 to the size of the simulated part, complete linear friction welding with the titanium alloy test block on a linear friction welding device, and complete the preparation of the diffusion welding-friction welding joint; Step 3: Process the composite solid phase welding test block into a composite solid phase process test piece according to the design drawing.

2. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: The titanium alloy test piece I and the titanium alloy test piece II are hollow sheet-like titanium alloys, and the titanium alloy test block is a solid titanium alloy block.

3. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: The flatness in step 1 reaches 0.02 mm.

4. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: In the preparation of the diffusion welding joint in step 1, the diffusion welding furnace is heated to 800° C.-900° C., a pressure of 2 MPa-5 MPa is applied, and the furnace is taken out after keeping the temperature for 2-3 hours.

5. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: The welding parameters of the linear friction welding in step 2 are: pressure 60MPa-100MPa, frequency 30Hz-60Hz, amplitude 2mm-3mm.

6. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: The specific method of processing the diffusion welding joint to the size of the simulated part in step 2 is: First, the surface where the diffusion weld is located is taken as the symmetry plane, and material is evenly removed on both sides of the diffusion welding joint; the surface on the diffusion welding joint that is perpendicular to the diffusion weld is used as the welding surface of the linear friction welding, and the processing is stopped when the length and width of the welding surface of the linear friction welding are the same as those of the titanium alloy test block, so that the welding surface of the diffusion welding joint is the same size as the welding surface of the titanium alloy test block.

7. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: The linear friction weld in step 2 is arranged in a T-shape with the diffusion weld in step 1.

8. The method for preparing a composite solid phase welding process test piece according to claim 1, characterized in that: The composite solid phase process test piece in step 3 is divided into two parts: a vibration part and a clamping part. The titanium alloy test piece I and the titanium alloy test piece II are the vibration part, and the titanium alloy test block is the fixed part. First, the linear friction weld is used as the boundary to complete the processing of the clamping part, and the processing size range is: height 55mm-57mm, width 49.9mm-50.1mm, thickness 4.5mm-5.5mm; then the diffusion weld is used as the center plane to complete the processing of the vibration part, and the processing size range is: height 69mm-71mm, width 29mm-31mm, thickness 25mm-27mm; the clamping part and the vibration part are transitioned by a circular arc.

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