CN103343205A - Method for controlling heat crack and residual stress of Fe-based fusion-repair layer via ultrasonic impact - Google Patents
Method for controlling heat crack and residual stress of Fe-based fusion-repair layer via ultrasonic impact Download PDFInfo
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- CN103343205A CN103343205A CN2013103086989A CN201310308698A CN103343205A CN 103343205 A CN103343205 A CN 103343205A CN 2013103086989 A CN2013103086989 A CN 2013103086989A CN 201310308698 A CN201310308698 A CN 201310308698A CN 103343205 A CN103343205 A CN 103343205A
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Abstract
The invention discloses a method for controlling the heat crack and residual stress of a Fe-based fusion-repair layer via an ultrasonic impact, which belongs to the field of process technology. The method comprises the following steps of: step 1, controlling installation for an ultrasonic impact gun for heat crack; step 2, controlling installation for an ultrasonic impact gun for residual stress; and step 3, performing impact treatment on the Fe-based self-fluxing alloy powder fusion-repair layer having a thickness of 0.5-3 mm during a welding process. The method disclosed by the invention has the following advantages that (1) the heat crack tendency of the Fe-based self-fluxing alloy powder fusion-repair layer caused by the difference of material parameters with matrix metal can be suppressed; (2) the surface residual tensile stress of the fusion-repair layer can be reduced, and the working life of a workpiece can be prolonged simultaneously; and (3) the crystalline grain diameter of the fusion-repair layer can be reduced, and the ductility and toughness of the fusion-repair layer can be improved based on improvement for the wear resistance of the fusion-repair layer.
Description
Technical field
The invention belongs to welding technology field, be specifically related to the molten method of repairing layer hot tearing and unrelieved stress of a kind of ultrasonic impact control Fe base.
Background technology
The repeated stress failure of material, wearing and tearing, corrosion and oxidation etc., it is general that the destruction of bringing thus and loss are very surprising, only corrode one all from the surface, the annual loss metal in the whole world reaches more than 100,000,000 tons.Therefore, adopt various surface strengthening technologies, improve the material surface performance, the reinforcement material surfacecti proteon all has very important meaning to fatigure failure, wearing and tearing and the corrosion of material.
But if resurfacing welding material is different with the body material composition, when built-up welding, must produce all transition layers inequality of a layer tissue and performance and base material or overlay cladding so.If this transition layer is fragility, must worsen the performance of overlay cladding so.In the weld deposit process, consistency and physical compatibility on the metallurgy between resurfacing welding material and the matrix material Tu are all extremely important.Whether compatiblely on the metallurgy depend in their mutual solubilities when liquid and solid-state and the built-up welding weldering process whether produce fragility mutually.Physicalies such as between the two temperature of fusion of the physical compatibility toe of resurfacing welding material and base material, the coefficient of expansion, thermal conductivity differ as far as possible little.Because these differences can influence thermal cycling process in the weld deposit process and the condition of crystallization, cause welding stress to increase, reduce the quality of junction.Be easy to produce some mass defects in the Fe base self-fluxing alloyed powder cladding process, as pore, be mingled with, crackle, component segregation etc.Cladding layer surface hardness height, splitting resistance is poor, and fowl has higher carbon, silicon and boron in the powdered alloy, and they and other alloying elements form alloy cpd, and these alloy cpd hardness are higher, and toughness is relatively poor, and the tendency that cracks is big.And postwelding exists bigger unrelieved stress, life-span of workpiece and postwelding processing is produced have a strong impact on.
The solution of cladding layer crackle is the starting point that is adjusted into the interpolation of alloying element and weldprocedure substantially, but is difficult to fundamentally solve the problem of overlay cladding crackle in actual welding is produced.And the adjustment of welding residual stress different because of the material parameter between cladding layer and base material make the mode that is difficult to adopt postweld heat treatment.So repair layer hot tearing and these processing methodes of unrelieved stress have some effects in that control Fe base self-fluxing alloyed powder is molten, but all exist limitation and inefficient problem.
The ultrasonic impact treatment technology, be to utilize the syringe needle that launches the at a high speed surface of striking work at room temperature, make skin-material produce bullet, viscous deformation, and by the vibration crystal grain thinning, thereby the surface engineering technology of raising workpiece surface intensity, plasticity and toughness, fatigue strength and stress corrosion resistant.
Summary of the invention
To reduce molten deficiency and the shortcoming of repairing the processing method of layer hot tearing and unrelieved stress of Fe base self-fluxing alloyed powder in order overcoming in the prior art to eliminate, to the invention provides a kind of efficient height, obvious results is applicable to the molten molten ultrasonic impact treatment process of repairing layer hot tearing and unrelieved stress control of Fe base self-fluxing alloyed powder that layer thickness is 0.5mm ~ 3mm of repairing.
A kind of ultrasonic impact reduces the molten method of repairing layer hot tearing and unrelieved stress of Fe base, carries out according to following steps:
The first step: the installation of the ultrasonic impact gun of control hot tearing: the ultrasonic impact gun of two control hot tearings is installed in apart from front end welding torch 35 ~ 40mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 3 ~ 4mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
Second step: the installation of the ultrasonic impact gun of control unrelieved stress: the ultrasonic impact gun of a control unrelieved stress is installed in apart from front end welding torch 100 ~ 120mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 5 ~ 6mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
The 3rd step: repair the molten layer of repairing of Fe base self-fluxing alloyed powder that layer thickness is 0.5mm ~ 3mm to melting, in welding process, adopt the ultrasonic impact gun of control hot tearing and the ultrasonic impact gun of control unrelieved stress to carry out shock treatment simultaneously: the ultrasonic impact gun that adopts the control hot tearing, utilize the pending zone of syringe needle high-speed impact, the impact head active position should comprise toe of weld and heat affected zone, adopt three syringe needles to impact, frequency of impact is 40KHz; Output rating 500W;
Adopt the ultrasonic impact gun of control unrelieved stress, utilize the pending zone of syringe needle high-speed impact, the impact head active position is repaiied a layer position for molten, adopts three syringe needles to impact, and frequency of impact is 20KHz, output rating: 600W; Treated Fe base self-fluxing alloyed powder is molten, and to repair layer hot tearing controlled, the no hot tearing appearance in surface; The vertical welding residual stress in repair place is reduced to original 5%.
The concrete parameter of shock treatment rifle of described control hot tearing is output rating: 500W; Output frequency: 40KHz; Output amplitude: 100um; The type of cooling: air-cooled; Processing speed: 0.1m ~ 0.3m/min; Voltage: AC, 220V, 50Hz.
The concrete parameter of the impact gun of described control unrelieved stress is: output rating: 600W; Output frequency: 20KHz; Output amplitude: 50um; The type of cooling: air-cooled; Processing speed: 0.1m ~ 0.3m/min; Voltage: AC, 220V, 50Hz.
Beneficial effect of the present invention:
1. compare with traditional hand bumping release unrelieved stress, ultrasonic impact technology has realized quantification, precision control, and processing parameter is stable, adjustable, has guaranteed the stability of process results and process.2. at molten hot tearing problem of repairing in the process, from controlling molten angle of repairing the amount of plastic deformation layer process of cooling, adopt ultrasonic impact to handle and reduced molten amount of plastic deformation of repairing layer, fundamentally suppressed the problem of hot tearing.3. the shock treatment in nearly seam district can produce oscillation action to the molten pool metal of crystallisation by cooling, thus refinement the molten crystal particle scale of repairing layer, improve its intensity and plasticity then.4. with traditional hand bumping or thermal treatment process relatively, the effect that ultrasonic impact treatment process adopts the spininess impact head to eliminate welding residual stress with weldering is obvious, can reduce more than 80%.
Description of drawings
Fig. 1 melts schematic representation of apparatus in the method for repairing layer hot tearing and unrelieved stress for ultrasonic impact control Fe base; Wherein 1 welding torch 2 is controlled the impact head of hot tearing ultrasonic impact guns, the impact head of 3 control unrelieved stress ultrasonic impact guns, the 4 molten layers, 5 workpiece repaiied;
Fig. 2 handles forward and backward meridional stress comparison diagram for the molten layer ultrasonic impact of repairing of Fe base self-fluxing alloyed powder.
Embodiment
The shock treatment rifle of control hot tearing of the present invention is the ultrasonic impact gun that market is bought, and its concrete parameter is output rating: 500W; Output frequency: 40KHz; Output amplitude: 100um; The type of cooling: air-cooled; Processing speed: 0.1m ~ 0.3m/min; Voltage: AC, 220V, 50Hz.
The impact gun of described control unrelieved stress is specially the ultrasonic impact gun that market is bought, and its concrete parameter is: output rating: 600W; Output frequency: 20KHz; Output amplitude: 50um; The type of cooling: air-cooled; Processing speed: 0.1m ~ 0.3m/min; Voltage: AC, 220V, 50Hz.
Embodiment 1
Be that the molten layer of repairing of the Fe302 self-fluxing alloyed powder of 1mm carries out ultrasonic impact and handles to thickness.May further comprise the steps:
The first step: the installation of the ultrasonic impact gun of control hot tearing: the ultrasonic impact gun of two row control hot tearings is installed in apart from front end welding torch 35mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 3mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
Second step: the installation of the ultrasonic impact gun of control unrelieved stress: the ultrasonic impact gun of a control unrelieved stress is installed in apart from front end welding torch 100mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 5mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
The 3rd step: repair the molten layer of repairing of Fe base self-fluxing alloyed powder that layer thickness is 1mm to melting, in welding process, adopt the ultrasonic impact gun of control hot tearing and the ultrasonic impact gun of control unrelieved stress to carry out shock treatment simultaneously: the ultrasonic impact gun that adopts the control hot tearing, utilize the pending zone of syringe needle high-speed impact, the impact head active position should comprise toe of weld and heat affected zone, adopt three syringe needles to impact, frequency of impact is 40KHz; Output rating 500W;
Adopt the ultrasonic impact gun of control unrelieved stress, utilize the pending zone of syringe needle high-speed impact, the impact head active position is repaiied a layer position for molten, adopts three syringe needles to impact, and frequency of impact is 20KHz, output rating: 600W;
Treated Fe base self-fluxing alloyed powder is molten, and to repair layer hot tearing controlled, the no hot tearing appearance in surface; The vertical welding residual stress in repair place is reduced to original 5%.By contrast through and not the ultrasonic impact of process handle the molten layer of repairing of Fe302 self-fluxing alloyed powder, the molten effect of repairing layer hot tearing and unrelieved stress of checking ultrasonic impact processing controls Fe base self-fluxing alloyed powder.Accompanying drawing 2 is seen in the molten welding residual stress comparative analysis of repairing workpiece of Fe base self-fluxing alloyed powder, and through the data contrast, welding residual stress drops to original 5% after overbump.。
Be that the molten layer of repairing of the Fe302 self-fluxing alloyed powder of 0.5mm carries out ultrasonic impact and handles to thickness.May further comprise the steps:
The first step: the installation of the ultrasonic impact gun of control hot tearing: the ultrasonic impact gun of two row control hot tearings is installed in apart from front end welding torch 40mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 3mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
Second step: the installation of the ultrasonic impact gun of control unrelieved stress: the ultrasonic impact gun of a control unrelieved stress is installed in apart from front end welding torch 110mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 5mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
The 3rd step: repair the molten layer of repairing of Fe base self-fluxing alloyed powder that layer thickness is 0.5mm to melting, in welding process, adopt the ultrasonic impact gun of control hot tearing and the ultrasonic impact gun of control unrelieved stress to carry out shock treatment simultaneously: the ultrasonic impact gun that adopts the control hot tearing, utilize the pending zone of syringe needle high-speed impact, the impact head active position should comprise toe of weld and heat affected zone, adopt three syringe needles to impact, frequency of impact is 40KHz; Output rating 500W;
Adopt the ultrasonic impact gun of control unrelieved stress, utilize the pending zone of syringe needle high-speed impact, the impact head active position is repaiied a layer position for molten, adopts three syringe needles to impact, and frequency of impact is 20KHz, output rating: 600W;
Treated Fe base self-fluxing alloyed powder is molten, and to repair layer hot tearing controlled, the no hot tearing appearance in surface; The vertical welding residual stress in ultrasonic impact position is reduced to original 5%.
Embodiment 3
Be that the molten layer of repairing of the Fe302 self-fluxing alloyed powder of 3mm carries out ultrasonic impact and handles to thickness.May further comprise the steps:
The first step: the installation of the ultrasonic impact gun of control hot tearing: the ultrasonic impact gun of two row control hot tearings is installed in apart from front end welding torch 37mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 4mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
Second step: the installation of the ultrasonic impact gun of control unrelieved stress: the ultrasonic impact gun of a control unrelieved stress is installed in apart from front end welding torch 120mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 6mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
The 3rd step: repair the molten layer of repairing of Fe base self-fluxing alloyed powder that layer thickness is 3mm to melting, in welding process, adopt the ultrasonic impact gun of control hot tearing and the ultrasonic impact gun of control unrelieved stress to carry out shock treatment simultaneously: the ultrasonic impact gun that adopts the control hot tearing, utilize the pending zone of syringe needle high-speed impact, the impact head active position should comprise toe of weld and heat affected zone, adopt three syringe needles to impact, frequency of impact is 40KHz; Output rating 500W;
Adopt the ultrasonic impact gun of control unrelieved stress, utilize the pending zone of syringe needle high-speed impact, the impact head active position is repaiied a layer position for molten, adopts three syringe needles to impact, and frequency of impact is 20KHz, output rating: 600W;
Treated Fe base self-fluxing alloyed powder is molten, and to repair layer hot tearing controlled, the no hot tearing appearance in surface; The vertical welding residual stress in ultrasonic impact position is reduced to original 5%.
Claims (3)
1. a ultrasonic impact reduces the molten method of repairing layer hot tearing and unrelieved stress of Fe base, it is characterized in that carrying out according to following steps:
The first step: the installation of the ultrasonic impact gun of control hot tearing: the ultrasonic impact gun of two row control hot tearings is installed in apart from front end welding torch 35 ~ 40mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 3 ~ 4mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
Second step: the installation of the ultrasonic impact gun of control unrelieved stress: the ultrasonic impact gun of a control unrelieved stress is installed in apart from front end welding torch 100 ~ 120mm place, ultrasonic impact gun is perpendicular to processed workpiece surface, the impact head diameter is 5 ~ 6mm, and the hardness of impacting syringe needle should guarantee to be not less than 55HRC;
The 3rd step: repair the molten layer of repairing of Fe base self-fluxing alloyed powder that layer thickness is 0.5 ~ 3mm to melting, in welding process, adopt the ultrasonic impact gun of control hot tearing and the ultrasonic impact gun of control unrelieved stress to carry out shock treatment simultaneously: the ultrasonic impact gun that adopts the control hot tearing, utilize the pending zone of syringe needle high-speed impact, the impact head active position should comprise toe of weld and heat affected zone, adopt three syringe needles to impact, frequency of impact is 40KHz; Output rating 500W; Adopt the ultrasonic impact gun of control unrelieved stress, utilize the pending zone of syringe needle high-speed impact, the impact head active position is repaiied a layer position for molten, adopts three syringe needles to impact, and frequency of impact is 20KHz, output rating: 600W; Treated Fe base self-fluxing alloyed powder is molten, and to repair layer hot tearing controlled, the no hot tearing appearance in surface; The vertical welding residual stress in repair place is reduced to original 5%.
2. a kind of ultrasonic impact according to claim 1 reduces the molten method of repairing layer hot tearing and unrelieved stress of Fe base, it is characterized in that the concrete parameter of shock treatment rifle of described control hot tearing is output rating: 500W; Output frequency: 40KHz; Output amplitude: 100um; The type of cooling: air-cooled; Processing speed: 0.1m ~ 0.3m/min; Voltage: AC, 220V, 50Hz.
3. a kind of ultrasonic impact according to claim 1 reduces the molten method of repairing layer hot tearing and unrelieved stress of Fe base, it is characterized in that the concrete parameter of impact gun of described control unrelieved stress is: output rating: 600W; Output frequency: 20KHz; Output amplitude: 50um; The type of cooling: air-cooled; Processing speed: 0.1m ~ 0.3m/min; Voltage: AC, 220V, 50Hz.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104862454A (en) * | 2015-05-22 | 2015-08-26 | 华中科技大学 | High-hardness material surface treatment method and device |
| CN108927521A (en) * | 2018-08-02 | 2018-12-04 | 北京工商大学 | Improve the equipment for after-treatment of 3D printing stainless steel work-piece surface roughness and intensity |
| CN111876585A (en) * | 2020-07-29 | 2020-11-03 | 北京理工大学 | Sound wave reduction homogenization regulation and control device and method in welding residual stress generation process |
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| CN101492759A (en) * | 2009-03-03 | 2009-07-29 | 南京工业大学 | Stress corrosion dehiscence resistant ultrasonic impact treatment process |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101492759A (en) * | 2009-03-03 | 2009-07-29 | 南京工业大学 | Stress corrosion dehiscence resistant ultrasonic impact treatment process |
Non-Patent Citations (1)
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| 阮家顺等: ""阳逻大桥钢锚箱焊缝超声冲击降低焊接残余应力工艺试验研究"", 《钢结构》, vol. 23, no. 3, 31 December 2008 (2008-12-31), pages 11 - 13 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104862454A (en) * | 2015-05-22 | 2015-08-26 | 华中科技大学 | High-hardness material surface treatment method and device |
| CN108927521A (en) * | 2018-08-02 | 2018-12-04 | 北京工商大学 | Improve the equipment for after-treatment of 3D printing stainless steel work-piece surface roughness and intensity |
| CN111876585A (en) * | 2020-07-29 | 2020-11-03 | 北京理工大学 | Sound wave reduction homogenization regulation and control device and method in welding residual stress generation process |
| US11919040B2 (en) | 2020-07-29 | 2024-03-05 | Beijing Institute Of Technology | Control device and control method for reducing and homogenizing welding residual stress by acoustic wave |
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