阅读说明：本技术 盖板及其制作方法和终端 (Cover plate and manufacturing method thereof and terminal ) 是由 周峰 李聪 李云刚 于 2021-08-16 设计创作，主要内容包括：本发明涉及电子产品零部件的技术领域,特别涉及一种盖板及其制作方法和终端。盖板的制作方法包括：将具有预设形状和尺寸的第一盖板模块叠放在第二盖板模块上的预设位置,制作叠片结构；将所述叠片结构置于第一预设温度下,使所述第一盖板模块与所述第二盖板模块的接触面熔接结合,制作锻坯；将所述锻坯置于大于所述第一预设温度的第二预设温度下,对所述锻坯进行热锻压塑形处理。上述方法避免熔接面应力集中造成塑形时玻璃断裂的现象,提高良品率,同时,成型方案简单。(The invention relates to the technical field of electronic product parts, in particular to a cover plate and a manufacturing method and a terminal thereof. The manufacturing method of the cover plate comprises the following steps: stacking a first cover plate module with a preset shape and size at a preset position on a second cover plate module to manufacture a lamination structure; placing the laminated structure at a first preset temperature, and enabling the contact surfaces of the first cover plate module and the second cover plate module to be welded and combined to manufacture a forging stock; and placing the forging stock at a second preset temperature higher than the first preset temperature, and carrying out hot forging and shaping treatment on the forging stock. The method avoids the phenomenon that the glass is broken when the fusion joint surface is shaped due to stress concentration, improves the yield, and has a simple forming scheme.)

1. The manufacturing method of the cover plate is characterized by comprising the following steps:

stacking a first cover plate module with a preset shape and size at a preset position on a second cover plate module to manufacture a lamination structure;

placing the laminated structure at a first preset temperature, and enabling the contact surfaces of the first cover plate module and the second cover plate module to be welded and combined to manufacture a forging stock;

and placing the forging stock at a second preset temperature higher than the first preset temperature, and carrying out hot forging and shaping treatment on the forging stock.

2. The method of making a cover plate of claim 1, wherein the first cover plate module is smaller in size than the second cover plate module.

3. The method for manufacturing a sheathing board according to claim 1, wherein the stacking of the first sheathing module having a predetermined size at a predetermined position on the second sheathing module comprises: and placing a positioning jig with a positioning opening on the second cover plate module, controlling the positioning opening to correspond to the preset position, and placing the first cover plate module in the positioning opening.

4. The method of manufacturing a cover plate according to claim 1, further comprising a step of first preheating the lamination stack before fusion bonding, the first preheating temperature being less than the first preset temperature.

5. The method for manufacturing a cover plate according to claim 1, wherein the first predetermined temperature is not less than an annealing point of the first cover plate module and not less than an annealing point of the second cover plate module, and the first predetermined temperature is not greater than a softening point of the first cover plate module and not greater than a softening point of the second cover plate module.

6. The method for manufacturing a cover plate according to claim 1, further comprising a step of subjecting the forging stock to a second preheating after the fusion bonding and before the hot forging and shaping process, the second preheating being at a temperature greater than the first preset temperature and less than the second preset temperature.

7. The method for manufacturing a cover plate according to claim 1, wherein the second predetermined temperature is not less than a softening point of the first cover plate module and not less than a softening point of the second cover plate module.

8. The method for manufacturing a cover plate according to claim 1, further comprising the step of annealing, cooling, polishing and/or tempering the product obtained after the hot forging and shaping process.

9. The method for manufacturing a cover plate according to claim 1, wherein the first cover plate module and the second cover plate module are made of glass;

the first preset temperature is 500-700 ℃, the welding and combining treatment is carried out at least once at the first preset temperature, the treatment time is 50-300 s each time, and the first preset temperature of each treatment is the same or different;

the second preset temperature is 700-1000 ℃, the hot forging and shaping treatment is carried out at least once at the second preset temperature, the treatment time is 50-300 s each time, and the second preset temperature of each treatment is the same or different.

10. The method for manufacturing a cover plate according to claim 9, further comprising a step of performing a first preheating on the lamination structure before the fusion bonding, wherein the temperature of the first preheating is lower than the first preset temperature, the temperature of the first preheating is 300 ℃ to 700 ℃, the first preheating is performed at least once, the processing time is 50s to 300s each time, and the temperature of the first preheating for each processing is the same or different; and/or

The method further comprises the step of carrying out second preheating on the forging stock after welding and bonding and before hot forging and shaping treatment, wherein the second preheating temperature is higher than the first preset temperature and lower than the second preset temperature, the second preheating temperature is 600-1000 ℃, the second preheating is carried out at least once, the treatment time is 50-300 s each time, and the second preheating temperatures of the treatments at each time are the same or different.

11. The method for manufacturing a cover plate according to claim 9, wherein the forging material is subjected to a pressure of 0.2Mpa to 0.9Mpa on the surface thereof during the hot forging and shaping process.

12. The method for manufacturing the cover plate according to any one of claims 1 to 11, wherein the forging stock is subjected to hot forging and shaping treatment by using a forming die, and the forming die comprises:

the upper die is provided with a first groove used for shaping the first cover plate module, and the upper die is also provided with a bulge used for pressing the second cover plate module; and

a lower die having a second groove for shaping the second cover plate module in cooperation with the protrusion,

the manufacturing method comprises the following steps: and placing the laminated structure in a forming cavity formed by the upper die and the lower die so as to manufacture a forging stock at the first preset temperature.

13. The method for manufacturing a cover plate according to claim 12, wherein the forming mold further includes a supporting mechanism, the supporting mechanism is disposed between the upper mold and the lower mold and located outside a forming cavity formed by the upper mold and the lower mold, the supporting mechanism can support the upper mold in an environment lower than the second preset temperature so that the upper mold has no self-weight pressure on the second cover plate module, and can deform or collapse under the self-weight pressure of the upper mold or under the preset pressure applied on the upper mold in the environment of the second preset temperature so that the upper mold applies a forging pressure on the second cover plate module.

14. A cover plate manufactured by the manufacturing method according to any one of claims 1 to 13.

15. A terminal comprising a circuit board assembly, a display assembly and the cover plate of claim 14, wherein the circuit board assembly is disposed in an interior space formed by the display assembly and the cover plate.

Technical Field

The invention relates to the technical field of electronic product parts, in particular to a cover plate and a manufacturing method and a terminal thereof.

Background

In the 5G era, the demand of consumers for mobile phones has shifted from the basic function field to the higher level field, and the product appearance has also upgraded from 2.5D, 3D to more complex forms. The cover plate with the crater shape integrates the rear-mounted camera glass lens with the traditional glass cover plate, has stronger integrity and better visual impact effect for people.

The existing volcanic vent modeling cover plate is mainly divided into two forms of equal thickness and unequal thickness. As shown in fig. 1, in the constant-thickness crater structure 03, since the back 301 of the crater has large fluctuation and is difficult to be coated with a film, color diversification can be realized only by coating and spraying, the color effect is single, and OC0 (shatter-proof resin liquid) needs to be sprayed as a protective layer to reinforce the glass. However, as the crater structure 04 with different thicknesses shown in fig. 2 has the crater back 401 and the cover plate concave 402 on the same plane, the film sticking is not affected, the film sticking difficulty is low, and the design of CMF (Color-Material-Finishing, Color, Material, and surface treatment) can be more diversified and is more popular with designers.

Disclosure of Invention

Therefore, the cover plate and the manufacturing method thereof provided by the invention can avoid the phenomenon of glass fracture during shaping caused by stress concentration of the welding surface, are beneficial to improving the yield, and meanwhile, the whole forming scheme is simple.

The technical scheme for solving the technical problems is as follows:

the manufacturing method of the cover plate is characterized by comprising the following steps:

stacking a first cover plate module with a preset shape and size at a preset position on a second cover plate module to manufacture a lamination structure;

placing the laminated structure at a first preset temperature, and enabling the contact surfaces of the first cover plate module and the second cover plate module to be welded and combined to manufacture a forging stock;

and placing the forging stock at a second preset temperature higher than the first preset temperature, and carrying out hot forging and shaping treatment on the forging stock.

The invention also provides a cover plate manufactured by the manufacturing method.

The present invention also provides a terminal comprising a circuit board assembly, a display assembly and the cover plate according to claim 13, wherein the circuit board assembly is disposed in an inner space formed by the display assembly and the cover plate.

Compared with the traditional scheme, the invention has the following beneficial effects:

according to the invention, the first cover plate module and the second cover plate module are firstly overlapped into a laminated structure, then the contact surfaces of the two modules are welded and combined at a first preset temperature, then the obtained forging blank is subjected to hot forging and shaping treatment, the forging blank can be deformed to a certain extent by the hot forging and shaping, in the process, the bonding force of the first cover plate module and the second cover plate module is favorably improved, the phenomenon that the subsequent shaped glass is fractured due to the stress concentration of the welding surface in the welding process in the previous step is also avoided, the yield is favorably improved, meanwhile, the 3D shape and the crater shape can be simultaneously extruded by the hot forging and shaping, the cover plates with different thicknesses of craters are obtained in one step, the forming scheme is simple, the transparent feeling is strong, and the crystal transparent effect is achieved.

Drawings

FIG. 1 is a cross-sectional view of a cover plate having a uniform thickness crater;

FIG. 2 is a cross-sectional view of a cover plate having craters of varying thicknesses;

FIG. 3 is a cross-sectional view of a lamination stack of one embodiment;

FIG. 4 is a front view of a lamination stack of one embodiment;

FIG. 5 is a schematic structural diagram of a cover plate forming mold according to an embodiment;

FIG. 6 is a schematic flow chart illustrating the forming steps of the cover plate according to one embodiment;

FIG. 7 is a cross-sectional view of a cover plate with varying thickness craters according to an embodiment;

FIG. 8 is a cross-sectional view of a terminal structure of one embodiment;

fig. 9 is a schematic view of a welding process of a comparative example.

Detailed Description

The present invention will be described in further detail with reference to specific examples. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Term(s) for

Unless otherwise stated or contradicted, terms or phrases used herein have the following meanings:

as used herein, the term "and/or", "and/or" includes any one of two or more of the associated listed items, as well as any and all combinations of the associated listed items, including any two of the associated listed items, any more of the associated listed items, or all combinations of the associated listed items.

In the present invention, the technical features described in the open type include a closed technical solution composed of the listed features, and also include an open technical solution including the listed features.

In the present invention, the directions or positional relationships indicated by "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., are based on the directions or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the present invention.

In the present invention, "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise

In the present invention, the terms "mounted," "connected," and "fixed" should be understood in a broad sense, for example, they may be fixedly connected, or detachably connected, or integrated; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, the first feature may be directly on or directly under the second feature, or the first and second features may be indirectly on or directly under each other through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It should also be understood that in explaining the connection relationship or the positional relationship of the elements, although not explicitly described, the connection relationship and the positional relationship are interpreted to include an error range which should be within an acceptable deviation range of a specific value determined by those skilled in the art. For example, "about," "approximately," or "substantially" may mean within one or more standard deviations, without limitation.

In the present invention, the numerical range is defined to include both end points of the numerical range unless otherwise specified.

The temperature parameter in the present invention is not particularly limited, and may be a constant temperature treatment or a treatment within a certain temperature range. The constant temperature process allows the temperature to fluctuate within the accuracy of the instrument control.

At present, the realization modes of the mass production of the craters with different thicknesses mainly comprise the following modes: 1) heating and bending a CNC crater;

2) adding a CNC heating bend at a welded volcanic vent; 3) and (4) bonding a volcanic vent and adding CNC. However, these manufacturing methods generally have the following problems:

1) CNC volcanic vent mainly uses thicker glass raw material, mills out the volcanic vent through CNC, if the volcanic vent height is higher, current glass raw material can't satisfy, then needs customize, and raw material is with high costs, and moreover, most raw material can mill through CNC and fall, and raw material utilization ratio is low, extravagant cost. Moreover, the requirement on a CNC machine table is high, the vibration of a main shaft is small, the machining time of the whole CNC is long, and the efficiency is low. And the knife line that CNC produced, the polishing degree of difficulty is big, and the glass after the polishing has dark probability of hindering big, and the reliability risk is higher. Moreover, if the 3D cover plate crater modeling needs to be realized, the 3D modeling needs to be made by hot bending the 2D plate with the crater milled.

2) The second method is mainly characterized in that small-size plane glass is welded on large-size plane glass, then the periphery of a crater is milled through CNC, an R angle is milled, and then 3D modeling is achieved through hot bending. The whole process is complex, the welding has high requirements on the flatness and cleanliness of glass, stress concentration easily exists on the edge of a welding surface, the fragment rate is high during hot bending, and the whole yield is low.

3) The bonding crater is formed by bending glass into a 3D shape, drilling holes on a 3D glass sheet and small-sized plane glass respectively, tempering the holes, bonding the small-sized plane glass on the 3D glass sheet through optical cement, and finally realizing the crater through CNC (computer numerical control), wherein the small-sized plane glass and the 3D glass sheet have high hole alignment requirements and can have certain dislocation. Moreover, the glue applying amount cannot be accurately controlled, and meanwhile, the glue has fluidity, is easy to overflow and is difficult to clean.

Based on the above, the invention provides the cover plate and the manufacturing method thereof, which can avoid various problems caused by a CNC (computer numerical control) process and a bonding process, and simultaneously avoid the phenomenon of glass fracture during shaping caused by stress concentration of a welding surface, thereby being beneficial to improving the yield, and simultaneously, the whole forming scheme is simple.

The manufacturing method of the cover plate of one embodiment comprises the following steps:

s1, preparing plane glass

In this embodiment, the first cover plate module and the second cover plate module are made of glass. The required graphic drawings are guided into a computer, a glass substrate is cut through large-scale glass carving equipment, a first cover plate module and a second cover plate module which are in preset shapes and sizes are obtained, the size of the first cover plate module is smaller than that of the second cover plate module, and the first cover plate module is used for forming a crater shape. The size of first apron module needs to be through the accurate calculation, adapts to the mould size, and the size undersize of first apron module can't laminate completely with the mould in the forming process, and the size of first apron module is too big, and the volcanic opening material is excessive, and because volcanic opening department withstands the mould for the unable mould of laminating completely of big face can cause the shaping not enough and the shadow is not in order.

S2. superposition

The surfaces of the first cover plate module and the second cover plate module are cleaned, the first cover plate module with the preset shape and size is positioned through the positioning jig, and the first cover plate module is stacked at the preset position of the second cover plate module, as shown in fig. 3 and 4. And placing a positioning jig 12 with a positioning opening on the second cover plate module 11, controlling the positioning opening to correspond to the preset position, and placing the first cover plate module 10 in the positioning opening. In the laminating process, the surrounding environment and the glass need to be kept clean, dust is prevented from entering a laminating surface, the front surface of the glass is prevented from being contacted by hands or gloves as far as possible, the laminating surface is prevented from being polluted, and the risk of pollutant generation is reduced by taking the glass through the side surface. The size of the positioning opening of the positioning jig 12 is 0.1mm larger than the edge of the first cover plate module, so that the first cover plate module is prevented from being clamped during lamination, the positioning jig is removed, and the lamination structure 01 is obtained.

In the lamination structure of this embodiment, the edge of the first cover plate module does not protrude from the edge of the second cover plate module, and the orthographic projection of the first cover plate module is located within the orthographic projection of the second cover plate module.

After the first cover plate module and the second cover plate module are overlapped, because the air of the contact surfaces of the two cover plate modules is extruded and exhausted, the two cover plate modules are not easy to generate relative displacement in the subsequent forming process.

S3, forming

Placing the laminated structure at a first preset temperature, and enabling the contact surfaces of the first cover plate module and the second cover plate module to be welded and combined to manufacture a forging stock;

and (3) placing the forging stock at a second preset temperature higher than the first preset temperature, and carrying out hot forging and shaping treatment on the forging stock.

Optionally, the first preset temperature is not less than an annealing point of the first cover plate module and not less than an annealing point of the second cover plate module, and the first preset temperature is not greater than a softening point of the first cover plate module and not greater than a softening point of the second cover plate module.

Optionally, the second preset temperature is not less than a softening point of the first cover plate module and not less than a softening point of the second cover plate module.

In this embodiment, the step of manufacturing the forging stock is completed by placing the lamination structure in a forming cavity of a forming die, the structure of the forming die is shown in fig. 5, the forming die 02 includes an upper die 20 and a lower die 21, and the upper die 20 and the lower die 21 cooperate to enclose the forming cavity. The proper matching gap between the glass and the mold is calculated according to the thermal expansion coefficient, so that the phenomenon that when the gap is too large, the glass inclines to one side in the forming process, the left and right or upper and lower arc height deviation of a formed product is too large, when the gap is too small, the glass is pushed to the mold and scratches the mold due to faster expansion, and in addition, in the process of rapid expansion, the stress cannot be rapidly released, and even the phenomenon of cracking can occur.

In this embodiment, the upper mold 20 has a protrusion 201 for pressing down the second cover plate module, a first flat surface portion 202, a first curved surface portion 203, and a first groove 204 for shaping the first cover plate module, the protrusion 201 is located on the first flat surface portion 202, and the first curved surface portion 203 smoothly connects groove walls of the first flat surface portion 202 and the first groove 204.

Through the setting, can make the plane between first apron module after the shaping and the second apron module be in the same direction as surely, need not further processing, avoid the step or connect the sword trace to remain, also further avoid the not in the same direction as scheduling problem of light shadow that follow-up polishing brought, the apron body after the shaping is felt strong, the wholeness is good.

In the present embodiment, the lower mold 21 has a second recess 211 for shaping the second cover module, a second flat surface portion 212, and a second curved surface portion 213 that are fitted with the protrusion 201, and the second curved surface portion 213 smoothly connects the second flat surface portion 212 and a shoulder of the second recess 211.

It will be appreciated that in other embodiments, the groove walls and groove bottoms of the first groove 204 may also be smoothly connected by a curved surface.

In this embodiment, the forming mold 02 further includes a supporting mechanism 22, the supporting mechanism 22 is disposed between the upper mold 20 and the lower mold 21 and located outside the forming cavity formed by the upper mold 20 and the lower mold 21, and the supporting mechanism 22 can deform or collapse under the self-weight pressure of the upper mold 20 or under the preset pressure applied to the upper mold 20 at an operating temperature of the forging blank to be formed, so that the upper mold 20 applies pressure to the forging blank to be formed.

An operating temperature of the forging stock to be formed may be referred to as a second preset temperature. In this embodiment, the supporting mechanism 22 can support the upper die 20 in an environment lower than the second preset temperature, so that the upper die 20 has no self-weight pressure on the second cover plate module, and can deform or collapse under the self-weight pressure of the upper die 20 or the preset pressure applied on the upper die 20 in the environment of the second preset temperature, so that the upper die 20 applies forging pressure on the second cover plate module, so as to place the lamination structure in a forming cavity formed by the upper die 20 and the lower die 21, so that the manufacturing of the forging blank is completed at the first preset temperature, and in the forming cavity, at the second preset temperature, the hot forging and shaping processing is completed.

It is understood that the deformation refers to the deformation of the supporting mechanism 22 under the pressure of the upper mold 20 due to its own weight or under the predetermined pressure applied to the upper mold 20 in the environment of the second predetermined temperature, and the supporting mechanism 22 may or may not recover the deformation under the conditions other than the above conditions. Alternatively, however, if the support mechanism recovers its shape during annealing, it is possible to eject the upper mold 20 to affect the consistency and stability of the cover plate profile and dimensions, at which point the support mechanism can recover its shape after demolding.

Alternatively, the support mechanism may be a disposable spring or a glass post.

The elastic recovery capability of the disposable spring is destroyed under certain temperature and pressure.

Alternatively, the softening point of the glass column should be close to or slightly higher than the lamination. The softening point is crossed lowly, then before first apron module and second apron module have not accomplished the butt fusion, takes place down couch under last mould dead weight for go up the mould and extrude the second apron module, take place the separation between two sheet glass. If the softening point is too high, the glass column props against the mold when the upper mold is pressed down, so that the mold cannot be smoothly pressed down, and final molding is affected.

Referring to fig. 6, a schematic flow chart of the forming step of the present embodiment is shown: and loading, namely putting the laminated structure 01 into a forming die, and then conveying the die into a continuous forming furnace for primary preheating, wherein the primary preheating temperature is 300-700 ℃, the primary preheating is carried out at least once, the processing time of each time is 50-300 s, and the primary preheating temperature of each time is the same or different. Specifically, the mold may be first preheated through 1-7 process stations.

After the first preheating, the die is placed at a first preset temperature, so that the contact surfaces of the first cover plate module and the second cover plate module are welded and combined to manufacture a forging stock, the first preset temperature is 500-700 ℃, the first preset temperature is higher than the first preheating temperature, the welding treatment is carried out at least once at the first preset temperature, the treatment time is 50-300 s each time, and the first preset temperatures of the treatments are the same or different. Specifically, the molds can be welded by 2-5 work stations.

And after the forging stock is manufactured by welding, carrying out second preheating on the die, wherein the temperature of the second preheating is 600-1000 ℃, the temperature of the second preheating is higher than the first preset temperature, the second preheating is carried out at least once, the processing time of each time is 50-300 s, and the temperature of the second preheating for each time is the same or different. Specifically, the mold is subjected to secondary preheating through 1-5 process stations.

And after the second preheating, placing the die at a second preset temperature, and performing hot forging and shaping treatment on the forging stock. The second preset temperature is 700-1000 ℃, the second preset temperature is higher than the second preheating temperature, hot forging and shaping treatment is carried out at least once at the second preset temperature, the treatment time is 50-300 s each time, and the second preset temperatures of the treatment of each time are the same or different. The temperature is too high, the stamp is heavy, and the edge frit may run down under gravity, affecting the forming. Specifically, the die is subjected to hot forging molding treatment through 2-5 process stations. When the hot forging and shaping are carried out, the pressure on the surface of the forging stock is 0.2-0.9 Mpa, the pressure is too low to extrude the glass, and the first cover plate module is filled in the first groove of the upper die; too high a pressure, a heavy stamp and a high risk of embossed spots.

And (5) annealing after hot forging and shaping treatment.

It is understood that annealing reduces the thermal stress of the glass by slow cooling. And during annealing, no pressure is applied to the mold any more, the supporting mechanism does not rebound at the moment, the mold is still in a mold closing state, and the mold is slowly cooled and the temperature is reduced in the mold closing state.

Optionally, the annealing temperature is 400-1000 ℃, the annealing temperature is lower than a second preset temperature, the annealing treatment is performed at least once, the treatment time is 50-300 s each time, and the annealing temperatures of the treatments are the same or different. Specifically, the mold is annealed through 2-10 process stations. Meanwhile, the warping of the formed product can be adjusted by adjusting the temperature difference between the upper die and the lower die, and optionally, the temperature difference between the upper die and the lower die is 0-100 ℃ in the annealing treatment. Too high temperature difference can cause the single surface of the glass to be cooled too fast, and thermal stress is generated to reduce the strength of the glass.

And after annealing, rapidly cooling the die to room temperature, performing cooling treatment at least once, wherein the treatment time is 50-300 s each time, and specifically, finishing the annealed die through 2-7 process stations. And (5) after cooling, opening the mold and taking out the molded product.

In this embodiment, in the step of S3, the temperature is uniformly raised to a first preset temperature to fuse and join the contact surfaces of the first cover plate module and the second cover plate module, after a period of processing, the temperature is uniformly raised to a second preset temperature, the forging stock is subjected to hot forging and shaping processing, after a period of processing, annealing is performed, and during annealing, the temperature is uniformly lowered to a temperature lower than the first preset temperature, then the forging stock is processed at the temperature for a period of time, and finally the forging stock is uniformly cooled to room temperature.

According to the invention, the first cover plate module and the second cover plate module are firstly overlapped into a laminated structure, then the contact surfaces of the two modules are welded and combined at a first preset temperature, and then the obtained forging blank is subjected to hot forging and shaping treatment, so that the forging blank can deform to a certain extent, in the process, the bonding force of the first cover plate module and the second cover plate module is favorably improved, the phenomenon that the subsequent shaped glass is fractured due to stress concentration of the welding surface in the previous welding and combining process is also avoided, the yield is favorably improved, meanwhile, the 3D shape and the crater shape can be simultaneously extruded through the hot forging and shaping, and the cover plate with craters with different thicknesses is obtained in one step. And various problems caused by CNC process and bonding can be avoided.

S4, polishing

Polishing refers to a process of reducing the roughness of a workpiece surface by mechanical, chemical, or electrochemical actions to obtain a bright, flat surface. And polishing the surface of the formed product to ensure that the surface is bright. Specifically, the concave surface and the convex surface of the product obtained in the previous step can be polished independently to obtain a product with a bright surface.

S5, tempering

And (3) placing the polished product in a sodium nitrate and potassium nitrate salt bath for ion exchange, so that ions with small radius in the glass are exchanged by ions with large radius in the salt bath, and a pressure stress layer is formed on the surface of the glass, thereby weakening the expansion of microcracks, further improving the strength of the glass, and obtaining the final product.

The cover plate with the craters with different thicknesses prepared by the method can also increase the thickness of glass at the crater modeling position, and compared with the conventional cover plate with the craters with different thicknesses, the thickness of the crater modeling is higher and the reliability is more excellent.

In addition, the cover plate with the craters with different thicknesses, which is prepared by the method, has the advantages that the convex surface of the cover plate glass is in the crater shape, the concave surface of the cover plate glass is a plane, the film sticking is not affected, and the CMF effect can be more diversified.

In one embodiment, by adjusting the shape of the molding die by the above method, the cover plate 04 having craters of different thicknesses as shown in fig. 7 can be obtained. Through moulding processing of hot forging and pressing, when extruding crater molding 41 and 3D molding 42 simultaneously, can guarantee that each bending department smooth transition, the molding is better.

In this embodiment, the height difference between the plane of the 3D model and the plane of the crater model is less than 3 mm.

In this embodiment, the orthographic projection of the crater model does not exceed the orthographic projection of the 3D model.

In this embodiment, the R angle of the 3D modeling plane connected to the outer side wall of the crater modeling is denoted as a first R angle 43, the R angle of the crater modeling plane connected to the inner side wall of the crater modeling is denoted as a second R angle 44, and the radius of the first R angle 43 is greater than 0.5mm, and the radius of the second R angle 44 is greater than 0.5 mm.

In this embodiment, the sectional area of the crater mold gradually decreases in a direction away from the perpendicular direction of the plane of the 3D mold.

The invention also provides a terminal, as shown in fig. 8, the terminal 06 includes a circuit board assembly 611, a display assembly 622 and the cover plate 604, and the circuit board assembly 611 is disposed in the inner space formed by the display assembly 622 and the cover plate 604.

In a comparative example, as shown in fig. 9, if the supporting mechanism is not provided in the mold, and in this state, the lamination structure is placed in the molding cavity defined by the upper mold 20 and the lower mold 21 and is placed at the first preset temperature, so that the contact surfaces of the first cover plate module and the second cover plate module are welded to make a forged blank, the upper mold 20 will contact the lamination structure under the pressure of its own weight, and the second cover plate module will warp and separate from the first cover plate module, resulting in a weak bonding phenomenon.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.