阅读说明：本技术 一种降低板带材残余应力的方法和装置 (Method and device for reducing residual stress of plate and strip ) 是由 宋克兴 林乙丑 周延军 康军伟 张彦敏 皇涛 杨婧钊 杜宜博 国秀花 刘海涛 张 于 2020-07-01 设计创作，主要内容包括：本发明涉及一种降低板带材残余应力的方法,属于板带材加工技术领域。该方法同时采用温度场、拉伸应力场和超声波振动应力场,对板带材进行降低残余应力处理,其中温度场条件为200-500℃,拉伸应力场条件为加载20-150MPa拉伸力,超声波振动应力场条件为加载18-30KHz的超声波振动。在三种条件的共同影响下,能够有效的使板带材产生微塑性变形,从而降低合金板带材残余应力,还能够保证板带材具有优良的力学性能、导电性能,能够满足连接器、引线框架等高端领域的产品需求。本发明还涉及一种降低板带材残余应力的装置。(The invention relates to a method for reducing residual stress of a plate strip, and belongs to the technical field of plate strip processing. The method simultaneously adopts a temperature field, a tensile stress field and an ultrasonic vibration stress field to carry out residual stress reduction treatment on the plate strip, wherein the temperature field condition is 200-500 ℃, the tensile stress field condition is that tensile force of 20-150MPa is loaded, and the ultrasonic vibration stress field condition is that ultrasonic vibration of 18-30KHz is loaded. Under the common influence of the three conditions, the sheet strip can be effectively subjected to micro plastic deformation, so that the residual stress of the alloy sheet strip is reduced, the sheet strip can be ensured to have excellent mechanical property and conductivity, and the product requirements in high-end fields such as connectors and lead frames can be met. The invention also relates to a device for reducing the residual stress of the plate strip.)

1. A method of reducing residual stress in sheet and strip material, comprising: meanwhile, the following conditions are adopted to carry out residual stress reduction treatment on the plate strip:

a. the temperature of the plate and strip is 200-500 ℃;

b. loading a tensile force of 20-150MPa in the length direction of the plate strip;

c. the plate and strip material is loaded with 18-30KHz ultrasonic vibration.

2. The method of reducing residual stress of a sheet and strip material of claim 1, wherein: the ultrasonic vibration loading is arc-shaped cylindrical surface loading, and the arc-shaped cylindrical surface loading covers the whole width direction of the plate strip.

3. The method of reducing residual stress of a sheet and strip material of claim 2, wherein: the arc-shaped cylindrical surface loading is arc-shaped cylindrical surface loading.

4. The method of reducing residual stress of a sheet and strip material of claim 1, wherein: the loading direction of the ultrasonic vibration is vertical plate strip loading, and the loaded compression stress is 50-2500N.

5. Method for reducing the residual stress of a sheet and strip according to any one of claims 1 to 4, characterized in that: the vibration amplitude of the ultrasonic vibration loading is 10-50 μm, and the ultrasonic power is 500-2500W.

6. The method of reducing residual stress of a sheet and strip material of claim 1, wherein: the residual stress reduction treatment is carried out under the protection of inert gas.

7. A device for reducing the residual stress of a plate strip is characterized in that: the method comprises the following steps:

the heating furnace is provided with a furnace wall and a furnace chamber surrounded by the furnace wall, and the furnace wall is provided with a first opening and a second opening for the plate strips to enter and exit the furnace chamber when in use;

the tension force loading device comprises a first winding roller and a second winding roller, and the first winding roller and the second winding roller are respectively positioned on the first opening side and the second opening side;

the ultrasonic loading device comprises a loading working head for applying ultrasonic vibration to the plate and strip materials in use, and the loading working head is positioned in a furnace chamber of the heating furnace.

8. The apparatus for reducing residual stress in sheet and strip material of claim 7, wherein: one of the first winding roller and the second winding roller is in transmission connection with a stretching driving device, and the other winding roller is in transmission connection with a braking device.

9. The apparatus for reducing residual stress in sheet and strip material of claim 7, wherein: and the first winding roller and the second winding roller are respectively connected with a first stretching driving device and a second stretching driving device in a transmission manner, and the power output ends of the first stretching driving device and the second stretching driving device are respectively provided with a braking device.

10. The apparatus for reducing residual stress in sheet and strip material of claim 7, wherein: the device also comprises a supporting platform, and the heating furnace and the stretching driving device are both arranged on the supporting platform.

11. The apparatus for reducing residual stress in sheet and strip material of claim 7, wherein: at least two groups of supporting roller sets which are alternately arranged by supporting rollers are also arranged in the furnace cavity.

12. The apparatus for reducing residual stress in sheet and strip material of claim 7, wherein: the heating furnace also comprises a movable furnace cover used for opening or closing the furnace cavity.

13. The apparatus for reducing residual stress of sheet and strip material as claimed in any one of claims 7 to 12, wherein: the loading working head is used for making contact with the plate and strip materials, and one surface of the loading working head, which is in contact with the plate and strip materials, is an arc-shaped cylindrical surface.

14. The apparatus for reducing residual stress of sheet and strip material as claimed in any one of claims 7 to 12, wherein: the ultrasonic loading device also comprises an ultrasonic transducer positioned outside the heating furnace and an amplitude transformer fixedly connected with the loading working head, and the amplitude transformer is inserted through the furnace wall of the heating furnace and fixedly connected with the ultrasonic transducer.

15. The apparatus for reducing residual stress in sheet and strip material of claim 14, wherein: the loading working head is positioned between the pair of near-end supporting rollers.

Technical Field

The invention relates to a device and a method for reducing residual stress of a plate strip, belonging to the technical field of plate strip processing.

Background

At present, the main methods for reducing the residual stress of the plate strip are stress relief annealing through an air cushion furnace, a bell jar furnace and the like, and the methods can generally control the residual stress of the alloy plate strip to be about +/-120 MPa and can only meet the technical field with low requirement on the residual stress. However, in the field of high-end thin strip materials, such as strip materials for high-end connectors and strip materials for lead frames, these strip materials are thin, and after an annealing process is adopted, the strip materials are warped, and the flatness of the strip materials is reduced, so that the use requirements cannot be met.

CN108405609B discloses an ultrasonic vibration auxiliary rolling method for producing low residual stress aluminum alloy strips, which comprises the steps of using aluminum alloy strips or medium plates as raw materials, firstly carrying out cold rolling to obtain strips or foils with the thickness of 10 mu m-2 mm, then utilizing three ultrasonic guide rollers with the same diameter to apply ultrasonic waves of 20 KHz-30 MHz to the strips or foils, and finally obtaining the low residual stress strips or foils. The method can reduce the residual stress of the strip or foil by cold rolling and ultrasonic treatment, but the reduction degree of the residual stress is limited, and according to the description of the specific embodiment of the patent document, the residual stress can be reduced by 75-80%, but the requirement of the high-end thin plate strip field is still difficult to meet.

Disclosure of Invention

The invention aims to provide a method capable of further reducing the residual stress of a plate strip. In addition, a device for reducing the residual stress of the plate strip is also provided.

The method for reducing the residual stress of the plate and strip adopts the following technical scheme: the method for reducing the residual stress of the plate strip comprises the following steps of simultaneously adopting the following conditions to carry out residual stress reduction treatment on the plate strip: a. the temperature of the plate and strip is 200-500 ℃; b. loading a tensile force of 20-150MPa in the length direction of the plate strip; c. the plate and strip material is loaded with 18-30KHz ultrasonic vibration.

The method for reducing the residual stress of the plate strip is suitable for the plate strip with the residual stress, in particular to the metal plate strip, such as a single metal plate strip, an alloy plate strip and the like, and the optimally suitable plate strip has the thickness less than or equal to 1.0mm and the width less than or equal to 100 mm.

In the method for reducing the residual stress of the plate strip, the specific process of reducing the residual stress of the whole plate strip is the prior art, namely, three conditions of the tensile stress field, the temperature field and the ultrasonic vibration stress field are applied to one end of the plate strip, and then the plate strip is pulled to continuously act on the other end, so that the residual stress of the whole plate strip is reduced. The process of pulling the plate and strip can be one time or repeated for a plurality of times. According to a further optimized scheme of the invention, the linear speed of the plate strip is 2.0-40 mm/s when the plate strip is pulled.

The method for reducing the residual stress of the plate strip adopts three conditions of a tensile stress field, a temperature field and an ultrasonic vibration stress field to be simultaneously applied to the plate strip. The plate and strip material can eliminate certain residual stress at certain heating temperature, especially at annealing temperature, the material atom activity of the plate and strip material is increased, the vacancy density is reduced, the distortion energy stored in the material is reduced, the strength of the plate and strip material can be reduced along with the temperature rise, the combined action of tensile stress and vibration stress is added on the basis, the micro plastic deformation can be easily generated on the surface metal of the plate and strip material, the action effect of the tensile stress and the ultrasonic vibration stress is more obvious at the moment, the action is more easily exerted, the effect of eliminating the residual stress by annealing is also existed at the same time, and the micro plastic deformation effect of the single treatment of the superposition of the two effects is better. The residual stress is reduced, the plate and strip materials can be guaranteed to have excellent mechanical property and conductivity, and the product requirements of high-end fields such as connectors and lead frames can be met.

Wherein the condition a: the temperature of the plate strip is 200-500 ℃, and the annealing temperature of the material is preferred.

The loading of the ultrasonic vibrations can be linear or surface loading, and the loading area covers the entire width of the sheet metal strip. The loading of the surface can adopt the arc cylindrical surface loading, the ultrasonic vibration is loaded on the plate and strip materials, meanwhile, the plate and strip materials can be bent in an arc surface, the plate and strip materials can be more fully influenced by the ultrasonic vibration loading, and the residual stress of the plate and strip materials can be further reduced. The preferred arc cylindrical surface loading is arc cylindrical surface loading.

The direction of ultrasonic vibration loading is vertical plate strip loading, and the loaded compression stress is 50-2500N.

In order to improve the treatment effect and the treatment efficiency, the vibration amplitude of the ultrasonic vibration loading is 10-50 μm, and the ultrasonic power is 500-2500W.

In order to protect the plate strip from oxygen oxidation in air during the annealing treatment, the residual stress reduction treatment is carried out under the protection of inert gas, and the inert gas is particularly and optimally selected to be nitrogen or argon.

The device for reducing the residual stress of the plate strip adopts the following technical scheme: an apparatus for reducing residual stress in a sheet and strip material, comprising: the heating furnace is provided with a furnace wall and a furnace chamber surrounded by the furnace wall, and the furnace wall is provided with a first opening and a second opening for the plate strips to enter and exit the furnace chamber when in use; the tension force loading device comprises a first winding roller and a second winding roller, and the first winding roller and the second winding roller are respectively positioned on the first opening side and the second opening side; the ultrasonic loading device comprises a loading working head for applying ultrasonic vibration to the plate and strip materials in use, and the loading working head is positioned in a furnace chamber of the heating furnace.

The device for reducing the residual stress of the plate strip can provide a tensile stress field, a temperature field and an ultrasonic vibration stress field for the plate strip at the same time, wherein the heating furnace is used for providing a temperature field condition for the plate strip, the tensile force loading device is used for providing a tensile stress field condition for the plate strip, and the ultrasonic loading device is used for providing an ultrasonic vibration stress field condition for the plate strip.

When the plate and strip loading device is used, two ends of a plate and strip are respectively wound on the first winding roller and the second winding roller, and opposite acting forces are applied to the plate and strip by rotating the first winding roller and the second winding roller, so that tensile stress is loaded on the plate and strip. The rotating force applied to the first roller and the second roller can be realized by the prior art, and the invention provides two optimized realization modes:

one of the first winding roller and the second winding roller is in transmission connection with a stretching driving device, and the other winding roller is in transmission connection with a braking device. Wherein drive arrangement is used for providing the rotatory power of winding up roller, and arresting gear is used for stablizing the tensile dynamics. In this way, the plate and strip can move in one direction between the tension drive and the brake when in use.

And secondly, a first stretching driving device and a second stretching driving device are respectively connected to the first winding roller and the second winding roller in a transmission manner, and braking devices are respectively arranged at power output ends of the first stretching driving device and the second stretching driving device. When the mode is adopted, the plate and strip materials can move bidirectionally between the two stretching driving devices, and the reciprocating operation is realized for multiple times, so that the treatment is more sufficient.

The specific optimization selection is carried out, the stretching driving device adopts a driving motor, and the formulating device adopts a magnetic powder brake.

The first winding roller and the second winding roller are respectively positioned on a first opening side and a second opening side of the furnace wall of the heating furnace, when in use, the plate and strip materials pass through the furnace chamber of the heating furnace through the first opening and the second opening, and the heating furnace can heat the plate and strip materials to raise the temperature.

The loading working head of the ultrasonic loading device is positioned in a furnace chamber of the heating furnace, and ultrasonic vibration is loaded to the plate and strip materials when the loading working head is used. The ultrasonic loading device generally comprises an ultrasonic transducer and an amplitude transformer fixedly connected with the ultrasonic transducer, wherein the amplitude transformer is inserted through the furnace wall of the heating furnace and fixedly connected with a loading working head, so that the use of the ultrasonic transducer is not influenced by the high temperature in the heating furnace.

The loading working head is transversely extended and can cover the whole width direction of the plate and strip materials when in use. The loading working head can be in a linear structure at one end used for being contacted with the plate and strip materials, and can also be preferably in an arc cylindrical surface, namely the longitudinal section of the loading working head is in an arc shape, so that the contact area with the plate and strip materials can be enlarged when the loading working head is used, and meanwhile, the plate and strip materials are subjected to arc bending deformation, and the residual stress of the plate and strip materials is further reduced. The arc-shaped cylindrical surface is optimally selected to be an arc-shaped cylindrical surface.

The heating furnace is characterized in that a pair of near-end supporting rollers for supporting the plate and the strip in use are further arranged in a furnace cavity of the heating furnace, and the loading working head is located between the pair of near-end supporting rollers. The pair of proximal support rollers is used for supporting the plate and strip material so that the loading working head can load, particularly apply compressive stress to the plate and strip material. After the pressing stress is applied, the plate and strip materials form a shape with two high ends and a low middle part at the local part, and the shape is similar to a V-shaped structure.

In addition, the device for reducing the residual stress of the plate strip of the invention has the following preferred improvements:

the device for reducing the residual stress of the plate strip further comprises a supporting platform, and the heating furnace and the stretching driving device are both arranged on the supporting platform. According to the specific optimized scheme, the supporting platform is supported by the supporting upright posts, the universal wheels are arranged at the bottoms of the supporting upright posts, the hand push rod is further arranged on the supporting upright post on one side, and therefore the whole equipment can be moved in the aspect.

The furnace cavity is also provided with at least two groups of supporting roller sets which are alternately arranged by the supporting rollers, when in use, the plate and strip materials are in an S shape under the action of the alternately arranged supporting rollers, on one hand, the same bending deformation effect can be generated on the upper surface and the lower surface of the plate and strip materials, on the other hand, the retention time of the plate and strip materials in the heating furnace is increased, and the full heating is realized.

The heating furnace also comprises a movable furnace cover for opening or closing the furnace chamber so as to load and unload the plate strip.

The material of the amplitude transformer and the loading working head adopts the material with better mechanical property in a heating state, such as titanium alloy and hard alloy.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the device for reducing residual stress of a plate and strip material of the present invention;

FIG. 2 is a schematic structural diagram of an embodiment of the ultrasonic loading device of the present invention.

Fig. 3 is a side view of fig. 2.

FIG. 4 is an enlarged partial schematic view of the loading head during operation.

The names of the components corresponding to the corresponding reference numerals in the drawings are:

1. the device comprises a first winding roller, 2, a first driving motor, 3, a supporting roller, 4, a plate and strip material, 5, an air inlet, 6, a heating furnace, 7, an ultrasonic transducer, 8, a double-end stud, 9, an amplitude transformer, 10, a near-end supporting roller, 11, a movable furnace cover, 12, an air outlet, 13, a tension sensor, 14, a right-angle speed changer, 15/22, a magnetic powder brake, 16, a supporting platform, 17, a supporting upright post, 18, a universal wheel, 19, a hand push rod, 20, a second winding roller, 21, a second driving motor, 23, a second opening, 24, a first opening and 25 for loading a working head.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that relational terms such as "first" and "second," and the like, which may be present in the embodiments of the present invention, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the statement that "comprises an … …" is intended to indicate that there are additional elements of the same process, method, article, or apparatus that comprise the element.

In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" when they are used are to be construed broadly, e.g., as meaning a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those skilled in the art from specific situations.

In the description of the present invention, unless otherwise specifically stated or limited, the term "provided" may be used in a broad sense, for example, the object of "provided" may be a part of the body, or may be arranged separately from the body and connected to the body, and the connection may be detachable or non-detachable. The specific meaning of the above terms in the present invention can be understood by those skilled in the art from specific situations.

The present invention will be described in further detail with reference to examples.