Welding method of stainless steel heating plate

Abstract

The invention relates to a welding method of a stainless steel heating plate, which comprises the following steps of: (1) fixing a heating plate body by using a welding tool, and shielding a non-welding area by using a shielding material; and (2) electron beam welding is conducted on the heating plate body fixed in the step (1), and the stainless steel heating plate is obtained. According to the welding method, the special welding tool is used for positioning, it is ensured that the air leakage part is stably centered, and welding deviation is avoided; an electron beam local repair welding technology is adopted, air leakage points are accurately cladded in a low heat input mode in a vacuum environment, and air tightness is repaired; and welding parameters are optimized to minimize thermal stress, so that the flatness of the product is kept.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heating disc welding, in particular to a welding method of a stainless steel heating disc. BACKGROUND

[0002] As a key heat source component, a heating disc needs to provide a highly uniform and stable temperature field for wafers or other substrates. Stainless steel heating discs have become an important material for high-end heating discs due to their excellent high-temperature resistance, corrosion resistance, and mechanical strength. A stainless steel heating disc is usually composed of multiple layers, with heating elements and temperature measuring elements integrated inside, and needs to be welded with high precision through vacuum brazing process. Vacuum brazing completes high-quality connection in an oxygen-free environment, avoids oxidation, and ensures welding strength and sealing performance. However, the coefficient of thermal expansion of stainless steel material is relatively high, which is easily affected by thermal stress during welding, leading to welding deformation. In addition, welding defects such as pores, incomplete penetration, or micro-cracks may cause air leakage after vacuum brazing, especially in critical sealing areas such as the maximum outer circle.

[0003] The work hardening characteristics of stainless steel limit the correction space after welding. Once vacuum brazing fails (such as air leakage or flatness out-of-tolerance), traditional methods often can only be scrapped, resulting in a huge waste of material cost, processing time, and equipment resources. According to statistics, the scrap rate of stainless steel heating discs at the vacuum brazing stage can reach 30% to 40%, significantly increasing the overall manufacturing cost and becoming a bottleneck problem restricting production efficiency and economic benefits.

[0004] CN110369835A discloses a welding process for S316L stainless steel pipes of a liquid cargo tank heating disc, including using V-shaped butt welds for segmented welding in the pipe circumferential direction; using manual tungsten argon arc welding, the welding gun moves horizontally between the two sides of the groove in the axial direction of the pipe to weld the base layer and the cover layer. The use of manual tungsten argon arc welding effectively improves the welding quality of the process pipe of the S316 stainless steel pipe of the heating disc.

[0005] CN118417661A discloses a welding method for an aluminum wafer heating disc, which first prepares a customized package for accommodating the aluminum wafer heating disc, the customized package includes a T-shaped package sleeve, a first cover plate, and a second cover plate, the first cover plate and the second cover plate correspond to the small opening and the large opening of the T-shaped package sleeve respectively; then the assembled aluminum wafer heating disc is sealed into the customized package, and the whole customized package after welding is sequentially degassed, hot isostatic pressing welded, and unpacked to complete the welding of the aluminum wafer heating disc. The use of hot isostatic pressing welding realizes the welding of the aluminum wafer heating disc with irregular structure.

[0006] However, for the air leakage defect after vacuum brazing, the above-mentioned existing repair welding methods (such as argon arc welding or laser welding) may introduce new thermal deformation due to local high temperature, further deteriorate the flatness, and even damage the internal functional structure. In addition, intergranular corrosion or embrittlement is prone to occur in stainless steel during secondary heating, which affects the long-term reliability of the component. Therefore, the industry urgently needs a special repair welding technology for vacuum brazing air leakage products, which can repair the air tightness while maximizing the geometric accuracy and functional integrity of the heating disc. SUMMARY

[0007] To solve the above technical problems, the present application provides a welding method for a stainless steel heating disc. The welding method of the present application uses a special welding tool for positioning to ensure that the air leakage position is stable and aligned, avoiding welding deviation; in addition, an electron beam welding process is used to precisely clad the air leakage point in a low heat input mode, thereby repairing the air tightness of the stainless steel heating disc. The welding method of the present application has high welding success rate, small disc body deformation, excellent protection effect, and the appearance of the finished product is consistent with that of normal products.

[0008] To achieve this purpose, the present application adopts the following technical solutions:

[0009] The present application provides a welding method for a stainless steel heating disc, which comprises:

[0010] (1) using a welding tool to fix the heating disc body, and using shielding material to shield the non-welding area;

[0011] (2) electron beam welding the heating disc body fixed in step (1) to obtain the stainless steel heating disc.

[0012] The welding method of the present application uses a special welding tool for positioning to ensure that the air leakage position is stable and aligned, avoiding welding deviation; in addition, an electron beam welding process is used to precisely clad the air leakage point in a low heat input mode, thereby repairing the air tightness of the stainless steel heating disc. The welding method of the present application has high welding success rate, small disc body deformation, excellent protection effect, and the appearance of the finished product is consistent with that of normal products.

[0013] As a preferred technical solution of the present application, the welding tool and the heating disc body are fixedly connected through threads in step (1).

[0014] Preferably, the welding tool is fixed on a three-jaw clamp.

[0015] Preferably, the shielding material comprises a high-temperature resistant adhesive tape.

[0016] As a preferred technical solution of the present application, step (1) further comprises polishing the heating disc body before fixing the heating disc body using the welding tool.

[0017] Preferably, the roughness of the heated disc body after the polishing treatment is less than 0.8 μm, such as 0.75 μm, 0.7 μm, 0.65 μm, 0.6 μm, 0.55 μm, 0.5 μm, 0.45 μm, etc., but not limited to the listed values, and other values not listed in the above range are also applicable.

[0018] Preferably, the flatness of the heated disc body is less than 0.1 mm, such as 0.09 mm, 0.008 mm, 0.07 mm, 0.06 mm, 0.05 mm, etc., but not limited to the listed values, and other values not listed in the above range are also applicable.

[0019] As a preferred technical solution of the present application, the electron beam welding in step (2) is performed under vacuum conditions; the vacuum degree of the electron beam welding is less than 10 -2 Pa, such as 0.5 x 10 -2 Pa, 1 x 10 -3 Pa, 1.5 x 10 -3 Pa, 2 x 10 -3 Pa, 2.5 x 10 -3 Pa, etc., but not limited to the listed values, and other values not listed in the above range are also applicable.

[0020] As a preferred technical solution of the present application, the electron beam focus of the electron beam welding in step (2) is immersion focus.

[0021] As a preferred technical solution of the present application, the electron beam welding in step (2) includes first electron beam welding and second electron beam welding performed in sequence.

[0022] In the present application, by adjusting the welding parameters of the first electron beam welding and the second electron beam welding, such as electron beam current and linear velocity, the thermal stress can be minimized, so as to maintain the flatness of the stainless steel heated disc.

[0023] As a preferred technical solution of the present application, the electron beam current of the first electron beam welding is 5-10 mA, such as 5 mA, 6 mA, 7 mA, 8 mA, 9 mA, 10 mA, etc., but not limited to the listed values, and other values not listed in the above range are also applicable.

[0024] Preferably, the immersion focus of the first electron beam welding is set to 3-5, such as 3, 3.5, 4, 4.5, 5, etc., but not limited to the listed values, and other values not listed in the above range are also applicable.

[0025] Preferably, the line speed of the first electron beam welding is 15-30 mm / s, for example 15 mm / s, 16 mm / s, 17 mm / s, 18 mm / s, 19 mm / s, 20 mm / s, 21 mm / s, 22 mm / s, 23 mm / s, 24 mm / s, 25 mm / s, 26 mm / s, 27 mm / s, 28 mm / s, 29 mm / s, 30 mm / s, etc., but not only limited to the listed values, other values not listed in the above value range are also applicable.

[0026] As a preferred technical solution of the present application, the molten pool width formed by the first electron beam welding is 2.1-3.2 mm, for example 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, etc., but not only limited to the listed values, other values not listed in the above value range are also applicable.

[0027] Preferably, the molten pool depth formed by the first electron beam welding is 1.3-2.0 mm, for example 1.3 mm, 1.4 mm, 1.5 mm, 1.5 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, etc., but not only limited to the listed values, other values not listed in the above value range are also applicable.

[0028] As a preferred technical solution of the present application, the electron beam current of the second electron beam welding is 15-20 mA, for example 15 mA, 16 mA, 17 mA, 18 mA, 19 mA, 20 mA, etc., but not only limited to the listed values, other values not listed in the above value range are also applicable.

[0029] Preferably, the focus setting of the second electron beam welding is 10-15, for example 10, 11, 12, 13, 14, 15, etc., but not only limited to the listed values, other values not listed in the above value range are also applicable.

[0030] Preferably, the line speed of the second electron beam welding is 15-30 mm / s, for example 15 mm / s, 16 mm / s, 17 mm / s, 18 mm / s, 19 mm / s, 20 mm / s, 21 mm / s, 22 mm / s, 23 mm / s, 24 mm / s, 25 mm / s, 26 mm / s, 27 mm / s, 28 mm / s, 29 mm / s, 30 mm / s, etc., but not only limited to the listed values, other values not listed in the above value range are also applicable.

[0031] As a preferred technical solution of the present application, the molten pool width formed by the second electron beam welding is 3.6-5mm, for example, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5mm, etc., but not limited to the listed values, and other values not listed in the above value range are also applicable.

[0032] Preferably, the molten pool depth formed by the second electron beam welding is 2.1-3.2mm, for example, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, etc., but not limited to the listed values, and other values not listed in the above value range are also applicable.

[0033] Compared with the prior art, the present application has at least the following beneficial effects:

[0034] The welding method of the present application ensures stable alignment of the air leakage position by positioning using a dedicated welding tool, avoiding welding deviation; in addition, the electron beam welding process is adopted to accurately clad the air leakage point in a low heat input mode, thereby repairing the air tightness of the stainless steel heating disc; by adjusting the welding parameters of the electron beam welding, the thermal stress can be minimized, thereby maintaining the flatness of the stainless steel heating disc; the welding method of the present application has high welding success rate, small disc deformation, excellent protection effect, and the appearance of the finished product is consistent with that of normal products. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 is a welding schematic diagram of a welding method of a stainless steel heating disc provided by the present application. DETAILED DESCRIPTION

[0036] The technical solutions of the present application will be further described below in conjunction with the drawings and through specific embodiments. However, the following examples are only simple examples of the present application, and do not represent or limit the protection scope of the present application, and the protection scope of the present application is subject to the claims.

[0037] Example 1

[0038] The present embodiment provides a welding method of a stainless steel heating disc, which comprises:

[0039] (1) polishing the heating disc body, the roughness of the heating disc body after polishing is 0.7 μm, and the flatness is 0.08 mm; a welding tool is used to fix the heating disc body, the welding tool and the heating disc body are fixedly connected through threads; the welding tool is fixed on a three-jaw clamp; and high-temperature-resistant adhesive tape is used to shield a non-welding area; and the assembly mode of the welding tool and the heating disc body is as shown in Figure 1

[0040] (2) under a vacuum condition with a vacuum degree of 0.5 × 10 -2 Pa, sequentially performing first electron beam welding and second electron beam welding on the fixed heating disc body in step (1); the electron beam focus of the electron beam welding is focus setting; the electron beam current of the first electron beam welding is 10 mA; the focus setting of the first electron beam welding is 5; the linear velocity of the first electron beam welding is 15 mm / s; the width of the molten pool formed by the first electron beam welding is 3.2 mm; and the depth of the molten pool formed by the first electron beam welding is 2.0 mm;

[0041] the electron beam current of the second electron beam welding is 20 mA; the focus setting of the second electron beam welding is 10; the linear velocity of the second electron beam welding is 15 mm / s; the width of the molten pool formed by the second electron beam welding is 5 mm; and the depth of the molten pool formed by the second electron beam welding is 3.2 mm, to obtain the stainless steel heating disc.

[0042] Example 2

[0043] The embodiment provides a welding method of a stainless steel heating disc, and the welding method comprises the following steps:

[0044] (1) polishing the heating disc body, the roughness of the heating disc body after polishing is 0.6 μm, and the flatness is 0.07 mm; a welding tool is used to fix the heating disc body, the welding tool and the heating disc body are fixedly connected through threads; the welding tool is fixed on a three-jaw clamp; and high-temperature-resistant adhesive tape is used to shield a non-welding area;

[0045] (2) under a vacuum condition with a vacuum degree of 1 × 10 -3 Pa, sequentially performing first electron beam welding and second electron beam welding on the fixed heating disc body in step (1); the electron beam focus of the electron beam welding is focus setting; the electron beam current of the first electron beam welding is 8 mA; the focus setting of the first electron beam welding is 4; the linear velocity of the first electron beam welding is 20 mm / s; the width of the molten pool formed by the first electron beam welding is 2.5 mm; and the depth of the molten pool formed by the first electron beam welding is 1.7 mm;

[0046] ​The electron beam current of the second electron beam welding is 18 mA; the focus setting of the second electron beam welding is 12; the linear velocity of the second electron beam welding is 20 mm / s; the width of the molten pool formed by the second electron beam welding is 4.2 mm; the depth of the molten pool formed by the second electron beam welding is 2.5 mm, and the stainless steel heating disc is obtained.

[0047] Example 3

[0048] The embodiment provides a welding method of a stainless steel heating disc, and the welding method comprises the following steps:

[0049] (1) polishing treatment is performed on the heating disc body, the roughness of the heating disc body after the polishing treatment is 0.5 μm, and the flatness is 0.06 mm; a welding tool is used to fix the heating disc body, the welding tool and the heating disc body are fixedly connected through threads; the welding tool is fixed on a three-jaw clamp; and high-temperature-resistant adhesive tape is used to shield a non-welding area;

[0050] (2) under the vacuum condition that the vacuum degree is 2*10 -3 Pa, first electron beam welding and second electron beam welding are sequentially performed on the fixed heating disc body in step (1); the electron beam focus of the electron beam welding is a focus setting; the electron beam current of the first electron beam welding is 5 mA; the focus setting of the first electron beam welding is 3; the linear velocity of the first electron beam welding is 30 mm / s; the width of the molten pool formed by the first electron beam welding is 2.1 mm; and the depth of the molten pool formed by the first electron beam welding is 1.3 mm;

[0051] The electron beam current of the second electron beam welding is 15 mA; the focus setting of the second electron beam welding is 15; the linear velocity of the second electron beam welding is 30 mm / s; the width of the molten pool formed by the second electron beam welding is 3.6 mm; the depth of the molten pool formed by the second electron beam welding is 2.1 mm, and the stainless steel heating disc is obtained.

[0052] Example 4

[0053] The embodiment provides a welding method of a stainless steel heating disc, and the welding method comprises the following steps:

[0054] Example 5

[0055] The embodiment provides a welding method of a stainless steel heating disc, and the welding method comprises the following steps:

[0056] Example 6

[0057] The embodiment provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the linear speed of the first electron beam welding is adjusted to 10 mm / s, and other steps and condition parameters are the same as those of the embodiment 1.

[0058] Embodiment 7

[0059] The embodiment provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the linear speed of the first electron beam welding is adjusted to 40 mm / s, and other steps and condition parameters are the same as those of the embodiment 1.

[0060] Embodiment 8

[0061] The embodiment provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the electron beam flow of the second electron beam welding is adjusted to 12 mA, and other steps and condition parameters are the same as those of the embodiment 1.

[0062] Embodiment 9

[0063] The embodiment provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the electron beam flow of the second electron beam welding is adjusted to 25 mA, and other steps and condition parameters are the same as those of the embodiment 1.

[0064] Embodiment 10

[0065] The embodiment provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the linear speed of the second electron beam welding is adjusted to 10 mm / s, and other steps and condition parameters are the same as those of the embodiment 1.

[0066] Embodiment 11

[0067] The embodiment provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the linear speed of the second electron beam welding is adjusted to 40 mm / s, and other steps and condition parameters are the same as those of the embodiment 1.

[0068] Comparative Example 1

[0069] The comparative example provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the heating disc body is not fixed by using a welding tool in the step (1), and other steps and condition parameters are the same as those of the embodiment 1.

[0070] Comparative Example 2

[0071] The comparative example provides a welding method of a stainless steel heating disc, which is different from the embodiment 1 only in that the electron beam welding in the step (2) is replaced by an argon arc welding process, and other steps and condition parameters are the same as those of the embodiment 1.

[0072] Comparative Example 3

[0073] The comparative example provides a welding method of a stainless steel heating disc, which is only different from example 1 in that the electron beam welding in step (2) is replaced by a laser welding process, and other steps and condition parameters are the same as those of example 1.

[0074] Performance test

[0075] The flatness and air tightness of the stainless steel heating discs obtained in examples 1-11 and comparative examples 1-3 are tested, and the test results are shown in table 1.

[0076] Table 1

[0077]

[0078] It can be seen from the test results that:

[0079] (1) It can be seen from examples 1 to 3 that, by using a special welding tool for positioning and combining an electron beam welding process, the obtained stainless steel heating disc has good flatness and excellent sealing performance, and the disc body has small deformation.

[0080] (2) It can be seen from the comparison between example 1 and examples 4-11 that, by optimizing the electron beam current and linear velocity of the first electron beam welding and the second electron beam welding, the heat stress can be minimized, so that the stainless steel heating disc has good flatness and excellent sealing performance.

[0081] (3) It can be seen from the comparison between example 1 and comparative examples 1-3 that, in comparative example 1, the heating disc body is not fixed by using a welding tool, which cannot ensure the stable alignment of the air leakage position, so that the welding is deviated, resulting in poor sealing performance of the stainless steel heating disc; in comparative example 2, an argon arc welding process is used, which introduces new thermal deformation due to local high temperature, resulting in further deterioration of the flatness of the stainless steel heating disc; in comparative example 3, a laser welding process is used, which causes deformation of the disc body due to local high temperature, damages the internal functional structure of the stainless steel heating disc, and results in poor flatness and sealing performance of the stainless steel heating disc.

[0082] In summary, the present application provides a welding method of a stainless steel heating disc, which uses a special welding tool for positioning to ensure the stable alignment of the air leakage position and avoid welding deviation; in addition, an electron beam welding process is used to precisely clad the air leakage point in a low heat input mode, thereby repairing the air tightness of the stainless steel heating disc; by adjusting the welding parameters of the electron beam welding, the heat stress can be minimized, thereby maintaining the flatness of the stainless steel heating disc; the welding method of the present application has high welding success rate, small disc body deformation, excellent protection effect, and consistent appearance with normal products.

[0083] The applicant states that the above description is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and it should be understood by those skilled in the art that any changes or replacements within the technical scope disclosed by the present application can be easily thought out by those skilled in the art, and all of them fall within the protection scope and disclosure scope of the present application.

Claims

1. A welding method of a stainless steel heating pan, characterized by, The welding method comprises: (1) fixing the heating disc body using a welding tool, and shielding the non-welding area using shielding material; (2) performing electron beam welding on the fixed heating disc body in step (1) to obtain the stainless steel heating disc.

2. The welding method according to claim 1, characterized in that, In step (1), the welding tool and the heating disc body are fixedly connected through threads; Preferably, the welding tool is fixed on a three-jaw clamp. Preferably, the shielding material comprises high-temperature resistant adhesive tape.

3. The welding method according to claim 1 or 2, characterized in that, Before step (1), the heating disc body is further subjected to polishing treatment. Preferably, the roughness of the heating disc body after polishing treatment is less than 0.8 μm, and the flatness is less than 0.1 mm.

4. The welding method according to any one of claims 1 to 3, characterized in that, The electron beam welding of step (2) is performed under vacuum; the vacuum degree of the electron beam welding is less than 10 -2 Pa.

5. The welding method according to any one of claims 1 to 4, characterized in that, In step (2), the electron beam focus of the electron beam welding is a submerged focus.

6. The welding method according to any one of claims 1 to 5, characterized in that, In step (2), the electron beam welding comprises sequentially performed first electron beam welding and second electron beam welding.

7. The welding method according to any one of claims 1 to 6, characterized in that, The electron beam current of the first electron beam welding is 5-10 mA; Preferably, the submerged focus of the first electron beam welding is set to 3-5; Preferably, the linear velocity of the first electron beam welding is 15-30 mm / s.

8. The welding method according to any one of claims 1 to 7, characterized in that, The width of the molten pool formed by the first electron beam welding is 2.1-3.2 mm; Preferably, the depth of the molten pool formed by the first electron beam welding is 1.3-2.0 mm.

9. The welding method according to any one of claims 1 to 8, characterized in that, The electron beam current of the second electron beam welding is 15-20 mA; Preferably, the submerged focus of the second electron beam welding is set to 10-15; Preferably, the linear velocity of the second electron beam welding is 15-30 mm / s.

10. The welding method according to any one of claims 1 to 9, characterized in that, The width of the molten pool formed by the second electron beam welding is 3.6-5 mm; Preferably, the depth of the molten pool formed by the second electron beam welding is 2.1-3.2 mm.

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