Forge piece forming Ti2AlNb material bearing ring welding joint design method

Abstract

The invention discloses a forge piece forming Ti2AlNb material bearing ring welding joint design method, which comprises the following steps: firstly, designing a welding joint without a spigot, because of the high preheating temperature before welding, the welding joint is affected by expansion with heat and contraction with cold, and the welding joint without the spigot is easy to ensure the welding gap compared with the welding joint with the spigot; therefore, a welding joint structure without a seam allowance is adopted, and the gap of the welding joint is arranged, so that the assembly quality of the joint can meet the requirement of the welding gap under a high-temperature condition; and then through the design of the margins on the upper and lower surfaces of the welding joint, the near-surface dense pore defects in the high-temperature electron beam welding process can be effectively removed through turning.

Description

Technical Field

[0001] The invention belongs to the technical field of electron beam welding, and in particular relates to a design method for a welding joint of a bearing ring of a forged Ti2AlNb material. Background Art

[0002] As a special welding method, electron beam welding has the advantages of good welding accessibility, deep penetration, good atmosphere, high joint strength, small welding deformation, large welding thickness, and a wide range of weldable materials. It is increasingly used in the manufacturing process of precision parts.

[0003] Ti2AlNb material is a new type of lightweight and high temperature resistant material used to replace nickel-based heat resistant alloys. Ti2AlNb material has attracted attention due to its advantages such as high specific strength, high specific stiffness, high temperature mechanical properties and good oxidation resistance, but the connection technology is one of the key technologies for its application.

[0004] The study found that when electron beam welding of Ti2AlNb materials is performed, cracks and porosity defects will occur in the parts after welding when the cooling rate is high. Summary of the invention

[0005] The invention provides a design method for a forged Ti2AlNb material bearing ring welding joint, which solves the problem that cracks and pore defects will be generated after welding of parts when the cooling speed is relatively high.

[0006] To achieve the above object, the present invention provides the following technical solutions: A method for designing a welded joint of a forged Ti2AlNb material bearing ring, comprising: Design the welded joint as a welded joint without a stopper; Carry out preheating before welding and set the welding joint gap; Design the allowances on the front and back of the weld joint.

[0007] Preferably, the joint inclination angle of the weld joint without a stopper is 50°.

[0008] Preferably, the preheating temperature before welding is at least 800°C.

[0009] Preferably, the weld joint gap is an overfit.

[0010] Preferably, the maximum weld joint gap is 0.03 mm.

[0011] Preferably, the design of the margins on the front and back sides of the welded joint is specifically as follows: Combined with multiple groups of simulated specimens electron beam welding process tests, post-weld inspections were carried out to obtain the distribution law of weld porosity defects in the thickness direction, and the margins on the front and back of the welded joints were designed based on the distribution law.

[0012] Preferably, the weld porosity is less than or equal to 3 mm.

[0013] Preferably, the inspection performed after welding is CT inspection.

[0014] Preferably, the front margin of the weld joint is 3 mm. Preferably, the front side margin of the weld joint is equal to the back side margin.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a design method for a bearing ring weld joint of a forged Ti2AlNb material. First, a weld joint without a stopper is designed. Due to the high temperature preheating temperature before welding, the weld joint will be affected by thermal expansion and contraction. Compared with a weld joint with a stopper, a weld joint without a stopper is easier to ensure a welding gap. Therefore, the present invention adopts a weld joint structure without a stopper. Secondly, by setting the weld joint gap, it is ensured that under high temperature conditions, the joint assembly quality can meet the requirements of the welding gap. Then, by designing the upper and lower surface allowances of the weld joint, the near-surface dense pore defects during high-temperature electron beam welding can be effectively removed by machining. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flow chart of a method for designing a welding joint of a bearing ring of Ti2AlNb material formed by a forging according to the present invention.

[0017] Figure 2 It is a schematic diagram of the structure of the electron beam welded joint of the present invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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 part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0021] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0022] like Figure 1 As shown, the present invention provides a method for designing a welded joint of a bearing ring of a forged Ti2AlNb material, comprising: S101 designs the weld joint as a weld joint without a stopper; S102 performs preheating before welding and sets the welding joint gap; S103 Design the allowances on the front and back of the welded joint.

[0023] First, a welding joint without a stopper is designed. Due to the high preheating temperature before welding, the welding joint will be affected by thermal expansion and contraction. Compared with a welding joint with a stopper, a welding joint without a stopper is easier to ensure the welding gap. Therefore, the present invention adopts a welding joint structure without a stopper. Secondly, by setting the welding joint gap, it is ensured that under high temperature conditions, the joint assembly quality can meet the welding gap requirements. Then, by designing the upper and lower surface margins of the welding joint, the dense pore defects near the surface during high-temperature electron beam welding can be effectively removed by machining.

[0024] The joint inclination angle of the weld joint without a stopper is 50°.

[0025] A specific joint inclination angle (such as 50°) ensures good formation of the molten pool and uniformity of the weld during welding. This inclination helps reduce welding defects such as lack of fusion, slag inclusions, etc., and improves the strength and toughness of the welded joint.

[0026] The preheating temperature before welding is at least 800℃.

[0027] High temperature preheating can significantly reduce the residual stress generated during welding and reduce the risk of welding cracks. For high-performance materials such as Ti2AlNb, preheating can also help improve the weldability of the material, improve the quality of the weld and the overall performance of the joint.

[0028] The weld joint gap is overfit.

[0029] The overfit joint gap can ensure that the molten pool has enough space to fill during welding, while reducing welding defects (such as pores, lack of fusion, etc.) caused by excessive gaps. This helps to improve the density and strength of the welded joint.

[0030] The maximum gap of the welding joint is 0.03mm.

[0031] Strictly controlling the joint gap can ensure the stability of the welding process and the uniformity of the weld. Smaller gaps help reduce the heat-affected zone during welding, thereby reducing the risk of embrittlement of the welded joint and improving the fatigue strength of the joint.

[0032] The design of the margins on the front and back of the welded joint is as follows: Combined with multiple groups of simulated specimens electron beam welding process tests, post-weld inspections were carried out to obtain the distribution law of weld porosity defects in the thickness direction, and the margins on the front and back of the welded joints were designed based on the distribution law.

[0033] Through simulation tests and inspections, we can understand the distribution law of weld pores in the thickness direction, and design the allowance of the weld joint more specifically. This helps to reduce welding defects such as pores and improve the density of the weld and the overall quality of the joint.

[0034] The inspection performed after welding is CT inspection.

[0035] CT testing is a high-precision non-destructive testing method that can accurately detect defects inside welded joints (such as pores, cracks, etc.). This helps to detect and repair welding problems in a timely manner and ensure the quality and safety of welded joints.

[0036] The weld porosity is less than or equal to 3mm.

[0037] The positive allowance of the welding joint is 3mm. Reasonable margin design can ensure that the weld joint has sufficient material reserves during processing and use to cope with possible wear, corrosion or stress concentration. The 3mm margin may be the optimal value obtained after comprehensively considering factors such as the strength, toughness and processability of the weld joint.

[0038] The front allowance of the weld joint is equal to the back allowance.

[0039] Maintaining the consistency of the front and back allowances of the welded joint helps ensure the uniformity and symmetry of the joint. This can reduce stress concentration and deformation problems caused by uneven allowances and improve the overall stability and reliability of the welded joint.

[0040] Another embodiment of the present invention provides a method for designing a welded joint of a bearing ring of a forged Ti2AlNb material: 1. Design the welding joint structure according to the final size and angle of the welding joint in the design drawing. It can be designed into welding joint with stopper, welding joint without stopper, welding joint with stopper on the weld surface, welding joint with stopper on the back of the weld, and the optimal design is carried out according to the specific welding process; Since the high-temperature preheating temperature before welding is at least 800°C, the welding joint will be affected by thermal expansion and contraction. Compared with the welding joint with a stopper, the welding joint without a stopper is easier to ensure the welding gap. Therefore, the present invention adopts a welding joint structure without a stopper.

[0041] 2. The preheating temperature before welding should be at least 800℃. The gap requirement of the welding joint is overfitting, and the maximum gap should not exceed 0.03mm. The welding joint should ensure that the local temperature of the weld reaches 800℃ for welding, and the joint assembly quality meets the welding gap requirements; 3. The margin design of the front and back of the welding joint should be based on the final size of the design drawing, combined with multiple groups of simulated specimens electron beam welding process tests, and CT detection after welding to detect the distribution law of weld porosity defects in the thickness direction. Taking the welding joint of the present invention as an example, a 3mm machining margin is obtained for each of the upper and lower surfaces, which can effectively remove the dense porosity defects near the surface during high-temperature electron beam welding by machining; 4. Finally, a butt joint weld without welding stop is designed, which can meet the assembly quality requirements of high-temperature electron beam welding of parts, such as Figure 2 shown.

[0042] Although the embodiments of the present invention are described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments and application fields, and the above-mentioned specific embodiments are only illustrative and instructive, rather than restrictive. Under the guidance of the specification, a person skilled in the art can also make many forms without departing from the scope of protection of the claims of the present invention, all of which belong to the scope of protection of the present invention.

Claims

1. A method for designing a welded joint of a forged Ti2AlNb material bearing ring, characterized in that: include: Design the welded joint as a welded joint without a stopper; Carry out preheating before welding and set the welding joint gap; Design the allowances on the front and back of the weld joint.

2. The method for designing a forging-formed Ti2AlNb material bearing ring welded joint according to claim 1, characterized in that: The joint inclination angle of the weld joint without a stopper is 50°.

3. The method for designing a forging-formed Ti2AlNb material bearing ring welded joint according to claim 1, characterized in that: The preheating temperature before welding is at least 800℃.

4. The method for designing a forging-formed Ti2AlNb material bearing ring welded joint according to claim 1, characterized in that: The weld joint gap is overfit.

5. The method for designing a forging-formed Ti2AlNb material bearing ring welded joint according to claim 1, characterized in that: The maximum gap of the welding joint is 0.03mm.

6. The method for designing a forging-formed Ti2AlNb material bearing ring welded joint according to claim 1, characterized in that: The design of the margins on the front and back of the welded joint is as follows: Combined with multiple groups of simulated specimens electron beam welding process tests, post-weld inspections were carried out to obtain the distribution law of weld porosity defects in the thickness direction, and the margins on the front and back of the welded joints were designed based on the distribution law.

7. A method for designing a welded joint of a forged Ti2AlNb material bearing ring according to claim 6, characterized in that: The weld porosity is less than or equal to 3mm.

8. The method for designing a forging-formed Ti2AlNb material bearing ring welded joint according to claim 6, characterized in that: The inspection performed after welding is CT inspection.

9. A method for designing a welded joint of a forged Ti2AlNb material bearing ring according to claim 6, characterized in that: The positive allowance of the welding joint is 3mm.

10. A method for designing a welded joint of a forged Ti2AlNb material bearing ring according to claim 9, characterized in that: The front allowance of the weld joint is equal to the back allowance.

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