Shell preparation method, shell and electronic equipment

Abstract

The invention provides a preparation method of a shell, the shell and electronic equipment, and the preparation method of the shell comprises the steps that a metal casting is provided, the metal casting comprises a metal base body and a metal outer surface layer, the metal outer surface layer is located on the outer side of the metal base body and is adjacent to the metal base body, and holes are formed in the metal outer surface layer; and performing thermal deformation forging on the part, deviating from the metal matrix, of the metal outer surface layer to obtain the metal compact layer. The shell obtained through the preparation method does not need to be filled with materials, and the surface consistency of the shell is good.

Description

Technical Field

[0001] The present application relates to the technical field of electronic devices, and particularly to a method for manufacturing a housing, a housing, and an electronic device. Background Art

[0002] In current electronic devices on the market, holes are usually formed on the outer surface of the housing of the electronic device due to process problems, making the surface structure of the housing loose. Currently, it is common to use a putty process to fill the holes on the outer surface of the housing with a filling material to make the appearance surface of the housing have a better appearance effect. However, since the housing and the filling material are made of different materials, it is easy to cause poor adhesion of the filling material to the housing, and the surface consistency of the housing is relatively poor. Summary of the Invention

[0003] An object of the embodiments of the present application is to provide a method for manufacturing a housing, a housing, and an electronic device. The housing obtained by using this manufacturing method does not require a filling material, and the surface consistency of the housing is relatively good.

[0004] The embodiments of the present application provide a method for manufacturing a housing. The method for manufacturing the housing includes:

[0005] Providing a metal casting, the metal casting including a metal matrix and a metal outer layer. The metal outer layer is located outside the metal matrix and is adjacent to the metal matrix, and holes are formed in the metal outer layer;

[0006] Performing hot deformation forging on the part of the metal outer layer facing away from the metal matrix to obtain a metal dense layer.

[0007] In the method for manufacturing a housing provided by the embodiments of the present application, by performing hot deformation forging on the part of the metal outer layer in the metal casting facing away from the metal matrix, using the method of heating and deforming, the material in the part of the metal outer layer in the metal casting facing away from the metal matrix undergoes micro-flow, that is, the part close to the outer surface in the metal casting undergoes micro-flow. After flowing, the structure in the part of the metal outer layer facing away from the metal matrix is homogenized, and a metal dense layer is formed. At this time, during the hot deformation forging process, some of the holes on the outer surface of the metal casting and in the metal outer layer are closed, so as to achieve the closure of the holes on the outer surface of the obtained metal dense layer, and the porosity of the obtained metal dense layer is relatively low, which is beneficial to improving the appearance effect of the housing. In the method for manufacturing a housing provided by the embodiments of the present application, the holes in the metal dense layer formed by hot deformation forging are closed, and the obtained housing does not need to undergo a putty process, which is beneficial to improving the surface consistency of the housing. At the same time, compared with the above traditional process, it omits multiple putty and grinding links, the manufacturing process is simple, and the cost is low. In addition, by forming a metal dense layer by hot deformation forging the part of the metal outer layer facing away from the metal matrix, it is beneficial to improving the structural strength of the housing.

[0008] In a possible implementation manner, the step of hot-deforming and forging the portion of the metal outer layer away from the metal substrate to obtain the metal dense layer includes:

[0009] Performing hot deformation forging on the portion of the metal outer surface layer away from the metal substrate to obtain a metal hot deformation layer, wherein the metal hot deformation layer includes a metal dense layer and a metal surplus layer, and the metal surplus layer is located outside the metal dense layer;

[0010] The excess metal layer is removed to obtain the shell. By removing the excess metal layer, the outer surface of the shell is facilitated to achieve a hole-free appearance, thereby facilitating an improvement in the appearance of the shell.

[0011] In a possible implementation manner, the thickness of the metal residue layer is ΔH, and ΔH is 0.3 mm to 0.5 mm.

[0012] In a possible implementation, the shell further includes an appearance layer, and the method for preparing the shell further includes: preparing the appearance layer on the outer surface of the dense layer. Compared with the method in which the appearance layer is directly attached to the outer surface of the metal casting, a more stable gripping force can be formed between the metal dense layer and the appearance layer, and the metal dense layer can exhibit better wear resistance and resistance to the appearance layer falling off, which is conducive to improving the bonding ability between the metal dense layer and the appearance layer, thereby facilitating improving the appearance effect of the shell.

[0013] In a possible implementation manner, the temperature of hot deformation forging is 200°C to 300°C.

[0014] An embodiment of the present application also provides a shell, which includes a metal substrate, a metal dense layer and a metal adjacent layer. The metal dense layer is located on the outside of the metal substrate and is spaced apart from the metal substrate. The metal adjacent layer is fixedly connected between the metal substrate and the metal dense layer. Holes are formed in the metal dense layer and the metal adjacent layer. The porosity of the metal dense layer is smaller than the porosity of the metal adjacent layer.

[0015] In the shell provided by the embodiment of the present application, a metal dense layer is arranged on the outside of the metal substrate, and the porosity of the metal dense layer is less than the porosity of the metal adjacent layer, so that the surface structure of the metal dense layer is dense, the holes on the outer surface of the metal dense layer are small or even non-existent, and the metal dense layer does not need to be filled with filling materials, thereby avoiding the existing problem of needing to additionally fill the holes on the outer surface of the shell with filling materials, thereby avoiding the problem of the filling material having poor adhesion on the shell and being easy to fall off. At the same time, since the outer surface of the metal dense layer does not need to be filled with filling materials, the outer surface of the metal dense layer has better consistency, which is conducive to improving the appearance of the shell.

[0016] In a possible implementation manner, the porosity of the metal dense layer is ≤5%.

[0017] In a possible implementation, the pore diameter of the pores in the metal dense layer ≤ 50 μm.

[0018] In a possible implementation, the thickness of the metal dense layer is D, and D is 0.3 mm to 0.5 mm.

[0019] In a possible implementation, the housing further includes an appearance layer disposed on the outer surface of the metal dense layer. By providing the appearance layer, the surface gloss, color, etc. of the housing can be decorated.

[0020] The embodiment of the present application further provides an electronic device, including a functional module and the housing as described above, and the functional module is installed in the housing.

[0021] In a possible implementation, the housing is a middle frame, and the electronic device further includes a back cover, and the back cover is installed on the middle frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0023] Figure 1 It is a top view structural schematic diagram of the electronic device provided by the embodiment of the present application;

[0024] Figure 2 For Figure 1 It is a cross-sectional schematic diagram of a partial structure of the housing in the shown electronic device;

[0025] Figure 3 For Figure 2 It is a schematic diagram of the preparation process of the housing in the shown electronic device;

[0026] Figure 4 For Figure 3 It is a cross-sectional structural schematic diagram of the casting mold for casting to form a metal casting in the shown preparation process;

[0027] Figure 5 For Figure 3 It is a cross-sectional structural schematic diagram of the formed metal casting in the shown preparation process;

[0028] Figure 6 For Figure 5 It is a schematic diagram of the change of part A in the shown metal casting during hot deformation forging to form a metal substrate;

[0029] Figure 7 For Figure 6Schematic diagram of the change in removing the metal surplus layer and preparing the appearance layer of the metal casting after hot deformation forging Detailed implementation manners

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without making creative efforts belong to the scope of protection of the present application.

[0031] Please refer to Figure 1 , Figure 1 which is a top view structural schematic diagram of the electronic device 1 provided in the embodiment of the present application.

[0032] The electronic device 1 includes a functional module 100 and a housing 300, and the functional module 100 is installed in the housing 300. Among them, the electronic device 1 can be a device such as a mobile phone, a tablet computer, a computer (Personal Computer, PC), or a wearable device. The wearable device includes devices such as a watch or a bracelet. Exemplarily, the functional module 100 can be a display screen of the electronic device 1, and the housing 300 can be a middle frame of the electronic device 1.

[0033] In this embodiment, the electronic device 1 is taken as a mobile phone, the functional module 100 is taken as the display screen of the mobile phone, and the housing 300 is taken as the middle frame of the mobile phone for illustrative purposes. Among them, the electronic device 1 further includes a rear cover, and the rear cover is installed on the middle frame.

[0034] Refer to Figure 2 , Figure 2 which is Figure 1 a cross-sectional schematic diagram of a part of the structure of the housing 300 in the electronic device 1 shown.

[0035] The housing 300 includes a metal substrate 10 and an appearance layer 30, and the appearance layer 30 adheres to the outer surface of the metal substrate 10. Among them, the "metal" involved in the embodiments of the present application includes pure metals and metal alloys. Exemplarily, the material of the metal substrate 10 can be magnesium alloy or aluminum alloy.

[0036] Specifically, the outer surface of the metal substrate 10 includes an appearance surface 101 and a non-appearance surface 102. The non-appearance surface 102 is connected to the appearance surface 101. Among them, the appearance surface 101 of the metal substrate 10 refers to the outer surface of the metal substrate 10 that can be observed by the user in the assembled electronic device 1, and the non-appearance surface 102 refers to the outer surface of the metal substrate 10 that is not observed by the user in the assembled electronic device 1.

[0037] In the direction away from the outer side of the metal substrate 10 from the appearance surface 101 of the metal substrate 10, the metal substrate 10 sequentially includes a metal dense layer 11, a metal adjacent layer 13, and a metal matrix 15. The metal adjacent layer 13 is connected between the metal dense layer 11 and the metal matrix 15 to enable the metal adjacent layer 13 to be adjacent to the metal dense layer 11, and is located on the side of the metal dense layer 11 away from the outer side of the metal substrate 10. Specifically, the outer surface of the metal dense layer 11 is the outer surface of the metal substrate 10, and the outer surface of the metal dense layer 11 includes the appearance surface 101. Among them, holes 103 are formed in both the metal dense layer 11 and the metal adjacent layer 13. There are substantially no holes 103 in the metal matrix 15. In this embodiment, the hole diameter of the holes 103 in the metal dense layer 11 is ≤50 μm.

[0038] In the direction away from the outer side of the metal substrate 10 from the appearance surface 101 of the metal substrate 10, the thickness of the metal dense layer 11 is D. Exemplarily, D is 0.3 mm to 0.5 mm. Among them, the measurement method of the thickness of the metal dense layer 11 is as follows Figure 2 As shown, a cross-sectional tangential slice of the metal substrate 10 is made in the direction perpendicular to the appearance surface 101. The boundary between the metal dense layer 11 and the metal adjacent layer 13 is simulated in the area with holes 103, and the boundary line between the metal dense layer 11 and the metal adjacent layer 13 and the cross-sectional line of the appearance surface 101 is measured, and the distance therebetween is the thickness D of the metal dense layer 11.

[0039] In this embodiment, the metal dense layer 11, the metal adjacent layer 13, and the metal matrix 15 are of the same material. The porosity of the metal dense layer 11 is greater than the porosity of the metal matrix 15, and the porosity of the metal dense layer 11 is less than the porosity of the metal adjacent layer 13. In this embodiment, the porosity of the metal dense layer 11 is ≤5%. Among them, the calculation method of "the porosity of the metal dense layer 11" is as follows: According to the above measurement method, the boundary line between the metal dense layer 11 and the metal adjacent layer 13 drawn forms the area of the metal dense layer 11 with respect to the cross-sectional line of the appearance surface 101. In the area of the metal dense layer 11, the total area of the area of the metal dense layer 11 is S1, the area of a single hole 103 is S11, and the number of holes 103 is N1. The porosity of the metal dense layer 11 = the area of the holes 103 in the area of the metal dense layer 11 * the number of holes 103 / the total area of the area of the metal dense layer 11 = S11 * N1 / S1.

[0040] Similarly, the porosity of the metal adjacent layer 13 is calculated as follows: According to the above measurement method, draw the boundary line between the metal adjacent layer 13 and the metal matrix 15. The area between the boundary line between the metal dense layer 11 and the metal adjacent layer 13 and the boundary line between the metal adjacent layer 13 and the metal matrix 15 forms the area of the metal adjacent layer 13. Within the area of the metal adjacent layer 13, the total area of the area of the metal adjacent layer 13 is S2, the area of a single hole 103 is S22, and the number of holes 103 is N2. The porosity of the metal adjacent layer 13 = the area of the holes 103 within the area of the metal adjacent layer 13 * the number of holes 103 / the total area of the area of the metal adjacent layer 13 = S22 * N2 / S2.

[0041] The appearance layer 30 is attached to the outer surface of the metal dense layer 11, that is, attached to the surface of the metal dense layer 11 facing away from the metal adjacent layer 13, so as to realize the attachment of the appearance layer 30 to the appearance surface 101 of the metal substrate 10, and thus realize the attachment of the appearance layer 30 to the outer surface of the metal substrate 10. Among them, the appearance layer 30 can be used for decorative functions such as the surface gloss and color of the housing 300. Exemplarily, the appearance layer 30 can be an organic resin appearance layer. In this embodiment, the appearance layer 30 may include a primer layer, a middle paint layer, and a topcoat layer. The primer layer is attached to the outer surface of the metal dense layer 11, the middle paint layer is attached to the surface of the primer layer facing away from the metal dense layer 11, and the topcoat layer is attached to the surface of the middle paint layer facing away from the primer layer.

[0042] In the housing 300 provided by the embodiment of the present application, by providing the metal dense layer 11 on the outside of the metal matrix 15, and the porosity of the metal dense layer 11 is less than the porosity of the metal adjacent layer 13, the surface structure of the metal dense layer 11 is dense, and the holes on the outer surface of the metal dense layer 11 are small or even have no holes, so there is no need to fill the metal dense layer 11 with filling materials, avoiding the problem of filling the holes on the outer surface of the existing housing 300 with filling materials, and thus avoiding the problem that the filling materials are poorly adhered to the housing 300 and are prone to falling off. At the same time, since there is no need to fill the outer surface of the metal dense layer 11 with filling materials, the outer surface of the metal dense layer 11 has better consistency, which is beneficial to improving the appearance effect of the housing 300.

[0043] Refer to Figure 3 , Figure 3 is Figure 2 the schematic diagram of the preparation process of the housing 300 in the electronic device 1 shown.

[0044] The embodiment of the present application also provides a preparation method of the above housing 300, including:

[0045] S1. Provide a metal casting 110. Specifically, refer to Figure 4 , Figure 4 isFigure 3 Schematic cross-sectional structure diagram of the casting mold 120 for casting the metal casting 110 in the shown preparation process. Take the casting mold 120, which is provided with a cavity 121, a first opening 123 and a second opening 125. The cavity 121 is arranged inside the casting mold 120, and both the first opening 123 and the second opening 125 communicate with the cavity 121. Pour the molten metal raw material into the cavity 121 from the first opening 123, and the excess molten metal raw material can overflow from the second opening 125. The molten metal raw material fills the entire cavity 121 and cools and solidifies into the metal casting 110 in the cavity 121.

[0046] During the casting process of the metal casting 110, on the one hand, since the first opening 123 and the second opening 125 are in contact with the outer surface of the metal casting 110, gas is easily introduced from the first opening 123 and the second opening 125 into the part of the metal casting 110 close to the appearance surface (such as Figure 5 the metal outer layer 12 in the shown metal casting 110), thus easily causing holes 103 to be formed in the appearance surface and the part close to the appearance surface of the metal casting 110 after casting (see Figure 5 ). On the other hand, some substances contained in the metal raw material of the metal casting 110 can be vaporized at high temperatures, which will also cause holes 103 to be formed in the appearance surface and the part close to the appearance surface of the metal casting 110 (see Figure 5 ).

[0047] With reference to Figure 5 , Figure 5 is Figure 3 Schematic cross-sectional structure diagram of the formed metal casting 110 in the shown preparation process. From the outer surface of the metal casting 110 and in the direction away from the outside of the metal casting 110, the metal casting 110 successively includes a metal outer layer 12 and a metal matrix 15 adjacent to the metal outer layer 12. Among them, the metal outer layer 12 faces the outside of the metal casting 110, and holes 103 are formed in the metal outer layer 12. Exemplarily, the thickness of the metal outer layer 12 is W. Among them, the measurement of the thickness W of the metal outer layer 12 can refer to the measurement method of the thickness of the above-mentioned metal dense layer 11.

[0048] S2. Perform hot deformation forging on the part of the metal outer layer 12 facing away from the metal matrix 15 to obtain the metal dense layer 11. In this embodiment, the metal casting 110 is subjected to hot deformation forging to obtain the metal base material 10. Specifically, continue to refer to Figure 5, from the outer surface of the metal casting 110 and in a direction away from the outer side of the metal casting 110, the metal outer layer 12 includes a surface layer 124 and a metal adjacent layer 13. The surface layer 124 faces the outer side of the metal casting 110. The metal adjacent layer 13 is connected between the surface layer 124 and the metal matrix 15 to enable the metal adjacent layer 13 to be adjacent to the surface layer 124 and is located on the side of the surface layer 124 away from the outer surface of the metal casting 110. Among them, the surface layer 124 and the metal adjacent layer 13 are made of the same material, and a plurality of holes 103 are formed in both the surface layer 124 and the metal adjacent layer 13. Before hot deformation forging of the metal outer layer 12 in the metal casting 110, the boundary between the surface layer 124 and the metal adjacent layer 13 in the metal outer layer 12 is not obvious. The sizes of the plurality of holes 103 in the metal outer layer 12 are uneven and are irregularly distributed in the regions of the surface layer 124 and the metal adjacent layer 13.

[0049] Referring jointly to Figure 6 , Figure 6 is Figure 5Schematic diagram of the change of part A in the metal casting 110 during hot deformation forging to form the metal base material 10. The surface layer 124 in the metal outer surface layer 12 is subjected to hot deformation forging, and the surface layer 124 is extruded to form a metal dense layer 11, so as to realize the preparation of the metal base material 10 by hot deformation forging of the metal casting 110. Specifically, during the hot deformation forging of the metal casting 110, by heating and deforming the surface layer 124, the surface layer 124 is extruded to form a metal dense layer 11, and the material of the surface layer 124 in the metal outer surface layer 12 undergoes micro-flow. After the flow, the holes 103 on the outer surface of the metal casting 110 and in the surface layer 124 will close, while the holes 103 in the metal adjacent layer 13 basically remain unchanged, so as to realize that the porosity of the metal dense layer 11 is less than the porosity of the metal adjacent layer 13. Exemplarily, the temperature of the hot deformation forging is 200°C to 300°C. After the metal casting 110 is hot deformed and forged, the deformation amount of the metal dense layer 11 relative to the surface layer 124 in the thickness direction is ΔW, and ΔW is 0.3 mm to 0.5 mm, that is, the deformation amount ΔW of the metal base material 10 relative to the metal casting 110 in the thickness direction of the surface layer 124 is 0.3 mm to 0.5 mm. In this embodiment, the outer surface of the metal casting 110 includes a surface to be treated. During the hot deformation forging of the metal casting 110, the surface to be treated is extruded, so that the surface layer 124 is hot deformed and forged to form a metal hot deformation layer 126, and the surface to be treated of the metal casting 110 is formed into the appearance surface 101 of the metal base material 10. Exemplarily, before the metal casting 110 is hot deformed and forged, the thickness of the metal outer surface layer 12 can be 0.5 mm to 1.0 mm, that is, the thickness of the part of the metal casting 110 close to the surface to be treated of the metal casting 110 is 0.5 mm to 1.0 mm. Among them, the metal hot deformation layer 126 includes a metal dense layer 11 and a metal surplus layer 17. The metal dense layer 11 is connected between the metal adjacent layer 13 and the metal surplus layer 17, and the metal surplus layer 17 is located outside the metal dense layer 11.

[0050] Referring to Figure 7 , Figure 7 is Figure 6 a schematic diagram of the change of the metal casting 110 after hot deformation forging to remove the metal surplus layer 17 and prepare the appearance layer 30.

[0051] S3. Remove the metal surplus layer 17 to obtain the housing 300. In this embodiment, a CNC (Computerized Numerical Control) machining method is adopted to remove the metal surplus layer 17 in the metal thermal deformation layer 126 along the thickness direction of the metal thermal deformation layer 126. Exemplarily, the thickness of the metal surplus layer 17 is ΔH, where ΔH is 0.3 mm to 0.5 mm. After removing the metal surplus layer 17, the thickness of the metal dense layer 11 is D. By removing the metal surplus layer 17, it is beneficial to achieve the appearance effect of the outer surface of the metal substrate 10 without holes 103, improving the appearance effect of the metal substrate 10, and thus being beneficial to improving the appearance effect of the housing 300. It can be understood that the thickness of the metal surplus layer 17 can be adjusted according to actual needs.

[0052] S4. Prepare the appearance layer 30 on the outer surface of the metal dense layer 11. Exemplarily, the appearance layer 30 can be prepared by spraying or physical vapor deposition (PVD). In this embodiment, between step S4, there is also a step of polishing the outer surface of the metal dense layer 11 to remove the tool marks on the outer surface of the metal dense layer 11. In some embodiments, the polished metal substrate 10 can also be subjected to sandblasting anodic surface treatment to improve the adhesion of the appearance layer 30 on the outer surface of the metal dense layer 11 of the metal substrate 10, and at the same time, it can also improve the corrosion resistance and aesthetics of the metal substrate 10.

[0053] Take the housing 300 prepared in the embodiment of the present application as a simulation sample. After simulation, the reliability of the housing 300 such as bending resistance and drop resistance meets the requirements.

[0054] Currently, the main method for preparing metal castings 110 is by CNC (Computerized Numerical Control) machining, which has a long processing time and high processing costs. The embodiment of the present application provides a method for preparing a housing 300. By using casting to provide the metal casting 110, compared with the method of preparing metal castings 110 by CNC machining, the casting time is shorter and the cost is lower.

[0055] In addition, after casting, holes 103 are formed on the outer surface of the metal casting 110, which affects the appearance of the metal casting 110 and further affects the appearance of the housing 300. When preparing the housing 300 using the metal casting 110 by traditional processes, the metal casting 110 needs to be CNC machined first, then the outer surface of the metal casting 110 is polished. After that, the holes 103 on the outer surface of the metal casting 110 are filled with a filling material using a putty process, and baked to cure the filling material. Then, the outer surface of the metal casting 110 is polished again, and the above steps of puttying, baking, and polishing are repeated until the appearance of the metal casting 110 is qualified. Finally, an appearance layer 30 is coated on the outer surface of the metal casting 110 to prepare the housing 300. For the housing 300 prepared in this way, after removing the appearance layer 30 on the surface, the metal casting 110 is exposed. Using the HF acid etching method, the crystal structure of the metal casting 110 is exposed. The position of the putty can be clearly observed on the surface of the metal casting 110. There is an obvious boundary between the position where putty is applied and the position where no putty is applied. The surface consistency of the housing 300 is poor, the appearance is uneven, the manufacturing process is long, the appearance requires multiple polishings, puttyings, and bakings, the yield is low, and the preparation cost is high.

[0056] In the method for preparing the housing 300 provided by the embodiments of the present application, the part of the outer metal layer 12 of the metal casting 110 that faces away from the metal matrix 15 is processed by hot deformation forging. By means of heating and deformation, the material in the part of the outer metal layer 12 of the metal casting 110 that faces away from the metal matrix 15 undergoes micro-flow, that is, the part of the metal casting 110 close to the outer surface undergoes micro-flow. After the flow, the structure in the part of the outer metal layer 12 that faces away from the metal matrix 15 is homogenized, and a metal dense layer 11 is formed. At this time, during the hot deformation forging process, some of the holes 103 on the outer surface of the metal casting 110 and in the outer metal layer 12 are closed, so as to achieve the closure of the holes 103 on the outer surface of the obtained metal dense layer 11. The porosity of the obtained metal dense layer 11 is relatively low, which is beneficial to improving the appearance of the obtained metal substrate 10, and further beneficial to improving the appearance of the housing 300. In the method for preparing the housing 300 provided by the embodiments of the present application, the holes 103 of the metal dense layer 11 formed by hot deformation forging are closed. The prepared housing 300 does not require a putty process, which improves the surface consistency of the metal substrate 10, thus being beneficial to improving the surface consistency of the housing 300. At the same time, compared with the above traditional process, multiple puttying and polishing steps are omitted, the manufacturing process is simple, and the cost is low. In addition, by forming the part of the outer metal layer 12 that faces away from the metal matrix 15 into a metal dense layer 11 through hot deformation forging, the structural strength of the metal substrate 10 can also be improved, which is beneficial to improving the structural strength of the housing 300.

[0057] In addition, compared with the method in which the appearance layer 30 is directly attached to the outer surface of the metal casting 110, the portion of the metal outer layer 12 of the metal casting 110 in the embodiment of the present application that is away from the metal substrate 15 is extruded to form a metal dense layer 11. A more stable gripping force can be formed between the metal dense layer 11 and the appearance layer 30, and the metal dense layer 11 can exhibit better wear resistance and resistance to the appearance layer 30 falling off, which is beneficial to improving the bonding ability between the metal substrate 10 and the appearance layer 30, thereby helping to improve the appearance effect of the shell 300.

[0058] What is disclosed above is only a preferred embodiment of the present application, and it certainly cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A method for preparing a housing, characterized in that, The preparation method of the housing includes: Providing a metal casting, the metal casting includes a metal matrix and a metal outer layer, the metal outer layer is located outside the metal matrix and is adjacent to the metal matrix, and holes are formed in the metal outer layer; Performing hot deformation forging on the part of the metal outer layer facing away from the metal matrix to obtain a metal dense layer.

2. The manufacturing method of the housing according to claim 1, characterized in that, In the step of performing hot deformation forging on the part of the metal outer layer facing away from the metal matrix to obtain a metal dense layer, it includes: Performing hot deformation forging on the part of the metal outer layer facing away from the metal matrix to obtain a metal hot deformation layer, wherein the metal hot deformation layer includes a metal dense layer and a metal surplus layer, and the metal surplus layer is located outside the metal dense layer; Removing the metal surplus layer to obtain the housing.

3. The manufacturing method of the housing according to claim 2, characterized in that, The thickness of the metal surplus layer is ΔH, and ΔH is 0.3 mm to 0.5 mm.

4. The manufacturing method of the housing according to any one of claims 1 to 3, characterized in that, The housing further includes an appearance layer, and the preparation method of the housing further includes: preparing the appearance layer on the outer surface of the dense layer.

5. The manufacturing method of the housing according to any one of claims 1 to 3, characterized in that The temperature of the hot deformation forging is 200 °C to 300 °C.

6. A housing, characterized in that, The housing includes a metal matrix, a metal dense layer and a metal adjacent layer, the metal dense layer is located outside the metal matrix and is spaced from the metal matrix, the metal adjacent layer is fixedly connected between the metal matrix and the metal dense layer, holes are formed in both the metal dense layer and the metal adjacent layer, and the porosity of the metal dense layer is less than the porosity of the metal adjacent layer.

7. The housing according to claim 6, characterized in that, The porosity of the metal dense layer ≤ 5%.

8. The housing according to claim 6, wherein The pore diameter of the holes in the metal dense layer ≤ 50 μm.

9. The housing according to claim 6, characterized in that, The thickness of the metal dense layer is D, and D is 0.3 mm to 0.5 mm.

10. The housing according to any one of claims 6 to 9, characterized in that, The housing further includes an appearance layer, and the appearance layer is arranged on the outer surface of the metal dense layer.

11. An electronic device, characterized in that, Including a functional module and the housing according to any one of claims 6 to 10, and the functional module is installed in the housing.

12. The electronic device according to claim 11, wherein The housing is a middle frame, and the electronic device further includes a rear cover, and the rear cover is installed on the middle frame.

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