CN115214173A

CN115214173A - Shell, manufacturing method thereof and electronic equipment

Info

Publication number: CN115214173A
Application number: CN202110432532.2A
Authority: CN
Inventors: 滕双双; 吴献明
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2021-04-21
Filing date: 2021-04-21
Publication date: 2022-10-21

Abstract

The application discloses casing and manufacturing method, electronic equipment thereof, wherein the manufacturing method of the casing includes: obtaining a ceramic plastic composite substrate; pretreating the substrate to reduce the porosity of the substrate to a preset porosity; and after the pretreatment, carrying out copolymerization treatment on the base material so as to enable the ceramic particles in the base material to be crosslinked with the plastic, thereby obtaining the shell. Through the mode, the shell can present fine and smooth appearance, the risk of crushing the shell can be reduced, and the scratch resistance of the shell is improved so as to meet the use requirements of users.

Description

Shell, manufacturing method thereof and electronic equipment

Technical Field

The present disclosure relates to the field of housing technologies, and in particular, to a housing, a manufacturing method thereof, and an electronic device.

Background

With the development of technology and the improvement of consumption level of people, users have higher and higher requirements on the aspects of appearance, texture, performance and the like of articles for daily use, such as electronic equipment and the like.

Composite housings are becoming more and more popular with consumers for performance and appearance considerations.

Disclosure of Invention

The technical problem mainly solved by the application is to provide the shell, the manufacturing method of the shell and the electronic equipment, the fine appearance can be presented, the risk of crushing the shell can be reduced, and the scratch resistance of the shell is improved so as to meet the use requirements of users.

In order to solve the technical problem, the application adopts a technical scheme that: a manufacturing method of a shell is provided, and the manufacturing method of the shell comprises the following steps: obtaining a ceramic plastic composite substrate; pretreating the substrate to reduce the porosity of the substrate to a preset porosity; and after the pretreatment, carrying out copolymerization treatment on the base material so as to enable the ceramic particles in the base material to be crosslinked with the plastic, thereby obtaining the shell.

In order to solve the technical problem, the other technical scheme adopted by the application is as follows: providing a shell, wherein the shell comprises a base body, and the base body is made of a ceramic plastic composite material; wherein the porosity of the matrix is not greater than 0.5%.

In order to solve the above technical problem, the present application adopts another technical solution: provided is an electronic device including: a housing defining an accommodating space; the functional device is accommodated in the accommodating space; the shell is the shell or the shell manufactured by the manufacturing method.

The manufacturing method of the shell comprises the following steps: obtaining a ceramic plastic composite substrate; pretreating the base material to reduce the porosity of the base material to a preset porosity; after pretreatment, the base material is subjected to copolymerization treatment, so that the ceramic particles in the base material and the plastic are crosslinked together, and the shell is obtained. In the above manner, the porosity of the base material can be reduced by pretreating the base material to improve the density of the base material, so that on one hand, the pit defects of the base material can be reduced, and thus the shell presents a relatively fine appearance to meet the requirements of users on the appearance; on the other hand, the strength and the hardness of the shell can be improved, the risk of crushing the shell is reduced, and the scratch resistance of the shell is improved so as to meet the requirements of users on the performance of the shell.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts. Wherein:

FIG. 1 is a schematic structural diagram of an embodiment of an electronic device of the present application;

FIG. 2 is a schematic structural view of an embodiment of the housing of the present application;

FIG. 3 is a schematic flow chart diagram illustrating one embodiment of a method for making the housing of the present application;

FIG. 4 is a schematic flow chart of step S10 in FIG. 3;

FIG. 5 is a schematic flow chart of step S11 in FIG. 4;

FIG. 6 is a schematic flow chart of step S20 in FIG. 3;

fig. 7 is a partial schematic flow chart of an embodiment of a method for manufacturing a housing according to the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.

Referring to fig. 1, in an embodiment, an electronic device includes a housing 10 and a functional device 20. The housing 10 defines an accommodating space, and the accommodating space can be defined by the housing 10 and a screen of the electronic device. The functional device 20 is disposed in the accommodating space, and the housing 10 can protect the functional device 20 (e.g., a main board, a battery, etc.).

Specifically, the electronic device may be a mobile phone, a tablet computer, a notebook computer, an intelligent bracelet, an intelligent watch, and the like, and the housing 10 may be a front shell, a frame, a rear cover, and the like of the electronic device, which are not limited herein.

Referring to fig. 2, in one embodiment, the housing 10 may include a base 11 and one or more other layer structures formed on the base 11, such as a hardened layer 12 having a certain hardness to protect the housing, an anti-fingerprint layer 13 having an anti-fingerprint function, and the like; in another embodiment, the housing 10 may further include a light shielding layer for shielding light, a color layer having a certain color, a texture layer for exhibiting a texture effect, a reflective layer for reflecting incident light to exhibit a certain gloss, and the like as required; in other embodiments, the housing 10 may further include only the base 11, which is not particularly limited herein.

Specifically, the material of the substrate 11 may be one of metal, ceramic, glass, plastic, and the like, or a composite material of two or more. In the present embodiment, the substrate 11 may be made of a ceramic plastic composite material.

Specifically, in one embodiment, the ceramic in the ceramic plastic composite material may be at least one of ceramics such as zinc oxide, zirconium oxide, aluminum oxide, silicon oxide, titanium oxide, and silicon carbide, and the plastic may be at least one of polyphenylene sulfide (PPS), polyphenylene sulfone resin (PPSU), polyamide (PA), and ethylene-vinyl acetate copolymer (EVA).

In practical application, the corresponding ceramic and plastic may be integrated by injection molding or the like to obtain the ceramic-plastic composite material, or the injection molded substrate may be further processed by other processing methods, which may be specifically selected according to practical situations, and is not limited herein.

The porosity of the matrix 11 may be not greater than 0.5%, and in some application scenarios, the porosity may satisfy 0.001% to 0.5%, specifically, may be 0.001%, 0.005%, 0.01%, 0.05%, 0.1%, 0.5%, and the like. The porosity of the matrix 11 is low, and the overall structure of the matrix 11 is dense.

It should be noted that, the porosity of the matrix of the ceramic plastic composite material in the related art is usually higher, which is more than 0.5%, even far more than 0.5%. When the porosity of the matrix is more than 0.5%, on one hand, the density is low, so that the hardness of the corresponding shell is low, for example, the pencil hardness under 1kg load is often below 2H, the Vickers hardness is only 50-60HV, the scratch resistance is poor in the using process, meanwhile, the strength of the shell is low, and particularly, under the condition of thin thickness, the shell is easy to break when being impacted by external force, so that the using requirement of a user is difficult to meet; on the other hand, after processing, dense pit defects are generated on the surface of the substrate, so that the substrate presents a rough appearance effect and the appearance requirement of a user is difficult to achieve. The porosity of the matrix 11 in the above embodiment of the present application can be less than 0.5%, even less than 0.1%, which on one hand can greatly improve the density of the matrix 11 of the shell, so as to greatly improve the strength and hardness of the shell 10, thereby improving the wear resistance and scratch resistance of the shell 10, and reducing the risk of the shell 10 breaking due to falling, thereby meeting the use requirements of users; on the other hand, the pit defect density can be reduced, so that the substrate 11 presents a fine appearance effect to meet the appearance requirements of users.

Accordingly, the hardness of the base 11 may be 4 to 9H, such as 4, 5, 6, 7, 8, 9H, etc., of the pencil hardness under a load of 1kg, which is much larger than 2H or less in the above-described related art; the strength can meet the extrusion force of 200-1000N under the thickness of 1mm, specifically 200N, 400N, 600N, 800N, 1000N and the like; the average grain size may be 50-1000nm, specifically 50nm, 100nm, 5000nm, 1000nm, etc. The base 11 has high strength and hardness, and thus can satisfy the performance requirements of the user on the housing 10.

Wherein, the average grain size can refer to the average grain size of the ceramic grains in the ceramic plastic composite material. Specifically, when the ceramic is a zirconia ceramic, the average grain size may refer to the average grain size of the zirconia grains; or when the ceramic is zinc oxide ceramic, the average grain size can refer to the average grain size of zinc oxide grains; when the ceramic is a complex phase ceramic, the average particle size of various crystal grains existing in the pre-fired ceramic can be referred to, and is not particularly limited herein.

In addition, the dielectric constant of the substrate 11 may be 4 to 8. Due to the small dielectric constant, the influence on signal shielding, signal loss and the like of applied electronic equipment is small. Specifically, the dielectric constant of the substrate 11 may be 4, 5, 6, 7, 8, etc.

That is to say, the ceramic-plastic composite material of the substrate 11 in the embodiment of the present application has a ceramic appearance, and has fewer pit defects, so as to exhibit a fine appearance effect; in terms of performance, the porosity is low, so that the shell 10 has good wear resistance and scratch resistance and low breakage risk; meanwhile, the signal influence on the applied electronic equipment is small, and further the signal intensity of the electronic equipment is improved to a certain extent, so that the shell 10 in the application can meet the use requirements of users in the aspects of appearance, physical performance and the signal intensity influence on the electronic equipment.

Specifically, referring to fig. 3, in one embodiment, the method for manufacturing the housing of the present application may include:

step S10: obtaining a ceramic plastic composite substrate;

the ceramic-plastic composite substrate can be a substrate obtained by compounding and molding a ceramic material and plastic. In the related art, the substrate can be directly used to fabricate the housing 10.

Specifically, referring to fig. 4, in one embodiment, step S11 may include:

step S11: obtaining ceramic powder infiltrated by an acetic acid solution;

it should be noted that the ceramic powder used for preparing the ceramic-plastic composite substrate in the present embodiment is a ceramic powder that has been soaked in an acetic acid solution in advance. Because the ceramic particles in the ceramic powder are soaked by the acetic acid solution in advance, at least part of the ceramic particles in the ceramic powder can be wrapped by the acetic acid, so that the ceramic particles are prevented from being tightly wrapped by the modifier during subsequent modification treatment, and the acetic acid can be contacted with the ceramic particles during subsequent pretreatment of the base material, so as to provide support for the subsequent pretreatment.

Specifically, referring to fig. 5, in one embodiment, step S11 may include:

step S111: mixing a ceramic powder raw material with an acetic acid solution, and performing ball milling treatment to obtain ceramic powder to be treated;

in the step, the selected ceramic powder raw material is mainly pretreated. Specifically, the ceramic powder raw material may be at least one of nano zinc oxide, zirconium oxide, aluminum oxide, silicon oxide, titanium oxide, silicon carbide, and the like. Wherein the particle size of the ceramic powder raw material can be 20-1000nm, such as 20nm, 50nm, 100nm, 500nm, 1000nm, etc.; the topography may be spherical, spheroidal, irregular diamond, or other shapes, and is not limited herein.

When the ceramic powder raw material is pretreated, specifically, a certain mass of the ceramic powder raw material can be dissolved in 20-50% by mass of 0.5-5mol/L acetic acid solution according to requirements, then ball milling treatment is carried out for 0.5-24h, specifically, at least one of alumina balls, zirconia balls and the like can be used, and then the ceramic powder to be treated is obtained after filtration and drying.

Specifically, the mass fraction of the acetic acid solution may be 20%, 30%, 40%, 50%, etc.; the concentration of the acetic acid solution can be 0.5mol/L, 1mol/L, 3mol/L, 5mol/L and the like; the time for performing the ball milling treatment may be 0.5h, 1h, 2h, 4h, 8h, 16h, 24h, etc., and may be set according to the actual situation, which is not limited herein.

Step S112: modifying the ceramic powder to be treated to obtain ceramic powder slurry;

wherein, the ceramic powder to be treated can be modified by a modifier. Specifically, the ceramic powder to be treated, the modifier, the dispersant and the like may be mixed and dispersed, and then ball-milled to connect the modifier and the ceramic powder to be treated, thereby achieving modification treatment of the ceramic powder to be treated.

Specifically, the modifier used for modification treatment may be at least one of a silane coupling agent, ammonium citrate, polyacrylic acid, ammonium polymethacrylate, triethanolamine, and the like. It should be noted that the modifier can be specifically coupled with a hydroxyl group and other groups on the surface of the ceramic powder to be treated, so as to modify the ceramic powder to be treated, thereby improving the binding force of the ceramic powder to be treated in the subsequent bonding with plastic.

Wherein the dispersant is at least one selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), stearic acid, and ammonium stearate. Wherein, the addition of the dispersant enables the ceramic powder to be treated to be fully dispersed during modification treatment.

It should be noted that, in one embodiment, the ceramic powder to be treated may be colored according to actual requirements while being modified.

Wherein, the pigment for coloring the ceramic powder to be treated can be selected according to different color requirements of the shell 10. Specifically, the colorant may be an inorganic colorant, an organic colorant, a single colorant, or a mixture of two or more colorants. For example, when it is desired to color the ceramic powder to be treated black, at least one of iron oxide, cobalt oxide, manganese oxide, carbon black, and the like may be used.

Specifically, the ceramic powder to be treated, the modifier, the dispersant, the coloring material, and the like may be mixed together to perform both the modification treatment and the coloring treatment in the same process. Wherein, the mass percentages of the ceramic powder to be treated, the modifier, the dispersant and the pigment can be 20-70%, 0.1-3%, 0.1-1% and 1-20% in sequence.

Specifically, the mass percentage of the ceramic powder to be treated may be 20%, 30%, 40%, 50%, 60%, 70%, etc., the mass percentage of the modifier may be 0.1%, 0.5%, 1%, 2%, 3%, etc., the mass percentage of the dispersant may be 0.1%, 0.3%, 0.5%, 0.75%, 1%, etc., and the mass percentage of the colorant may be 1%, 5%, 10%, 15%, 20%, etc.

Further, after the materials are mixed to obtain a mixture, water and alumina and/or zirconia balls can be added for further mixing, and the mixture is subjected to ball milling and dispersion for 12-48 hours in a ball milling tank, so that the ceramic powder slurry subjected to modification treatment and coloring treatment is obtained.

Wherein, the mass ratio of the mixture, water and grinding balls can be 1-3; the time for ball milling and dispersing can be set to 12h, 21h, 30h, 39h, 48h and the like, and can be set according to actual conditions.

Of course, in other embodiments, the ceramic powder to be processed may be further processed according to actual requirements in the modification process.

Step S113: and granulating the ceramic powder slurry to obtain ceramic powder.

In order to facilitate subsequent molding with plastics, after ceramic powder to be treated is modified to obtain ceramic powder slurry, spray drying granulation can be further carried out to obtain ceramic powder.

Wherein, the granulation treatment can be carried out in a granulation tower. Specifically, the feeding temperature for granulation can be 70-80 ℃, the air inlet temperature can be controlled at 130-160 ℃, the air outlet temperature can be 70-85 ℃, the temperature in the tower can be controlled at 70-90 ℃, and the negative pressure in the tower can be 50-150pa.

Specifically, the feeding temperature may be 70 ℃, 72 ℃, 74 ℃, 76 ℃, 78 ℃, 80 ℃ or the like, the air inlet temperature may be controlled at 130 ℃, 140 ℃, 150 ℃, 160 ℃ or the like, the air outlet temperature may be 70 ℃, 75 ℃, 80 ℃, 85 ℃, the temperature inside the tower may be controlled at 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃ or the like, and the negative pressure inside the tower may be 50Pa, 70Pa, 90Pa, 110Pa, 130Pa, 150Pa or the like, and may be specifically set according to actual requirements.

Step S12: mixing ceramic powder and plastic and preparing a feed;

to prepare the ceramic-plastic composite substrate, the ceramic material and the plastic can be compounded together by injection molding or the like. For the convenience of subsequent molding, the obtained ceramic powder can be mixed with plastic in advance to prepare the feed.

Specifically, the plastic may be at least one of PPS, PPSU, PA, EVA, etc. as described above. Then mixing the ceramic powder and the plastic according to the mass ratio of 0.5-0.8. Specifically, the mass ratio of the two may be 5.

After mixing and batching, an internal mixer or a blending extruder can be further used for dispersing, specifically, the internal mixing or blending can be carried out for 2-5 times, specifically, 2 times, 3 times, 4 times, 5 times and the like, so that the materials are uniformly mixed, and then the extrusion granulation is carried out, thereby preparing the feed used for injection molding.

Step S13: the feedstock is shaped to provide a substrate.

Specifically, the feeding material may be molded by injection molding to obtain the ceramic plastic composite substrate in this embodiment, but may be implemented in other manners in other embodiments, which are not limited herein.

In some application scenarios, the feedstock obtained in step S12 may be directly fed into an injection machine for injection molding.

In other application scenarios, the feed needs to be dried before injection molding, and specifically, the feed can be dried at 90-150 ℃ for 8-12h. Wherein the drying temperature can be 90 ℃, 110 ℃, 130 ℃, 150 ℃ and the like, and the drying time can be 8h, 9h, 10h, 11h, 12h and the like.

After drying treatment, further injection molding in an injection machine, wherein the molding temperature can be controlled at 320-360 ℃, the injection speed can be controlled at 70-100%, the injection pressure can be controlled at 120-250MPa, the mold temperature can be controlled at 130-180 ℃, and the pressure maintaining time can be controlled at 2-60s. Specifically, the molding temperature may be 320 ℃, 330 ℃, 340 ℃, 350 ℃, 360 ℃ or the like, the injection rate may be 70%, 80%, 90%, 100% or the like, the injection pressure may be 120MPa, 150MPa, 200MPa, 250MPa or the like, the mold temperature may be 130 ℃, 140 ℃, 160 ℃, 180 ℃ or the like, the pressure holding time may be 2s, 5s, 10s, 20s, 40s, 60s or the like, and the setting may be performed in accordance with actual conditions.

Step S20: pretreating the base material to reduce the porosity of the base material to a preset porosity;

the voids herein can refer to the voids between the ceramic particles in the substrate, and the voids between the ceramic particles and the plastic. In practical applications, the substrate may be pretreated in various ways to reduce the porosity of the substrate, for example, the substrate may be heat treated.

In this embodiment, referring to fig. 6, step S20 may include:

step S21: putting the substrate into an acetic acid solution;

step S22: and heating the substrate, keeping the temperature after heating the substrate to a first temperature, and maintaining the pressure after pressurizing the substrate to a preset pressure.

In this embodiment, the first temperature for the heat treatment may be 70 to 110 ℃ and the holding time may be 0.5 to 12 hours. Specifically, the first temperature may be 70 ℃, 80 ℃, 90 ℃, 100 ℃, 110 ℃ or the like, and the holding time may be 0.5h, 1h, 3h, 6h, 9h, 12h or the like, which is not particularly limited herein.

Specifically, the preset pressure can be 120-180MPa, and the dwell time can be 0.5-12h. Specifically, the preset pressure may be 120MPa, 140MPa, 160MPa, 180MPa, etc., and the dwell time may be 0.5h, 1h, 3h, 6h, 9h, 12h, etc., which are not particularly limited herein. The pressing of the substrate may be performed using a hot isostatic pressing apparatus.

In the embodiment, the ceramic plastic composite substrate obtained after injection molding is placed in an acetic acid solution, and is subjected to heating and pressurizing treatment, so that the acetic acid solution can contact with the surfaces of the ceramic particles through pores of the substrate and chemically react with at least part of the surfaces of the ceramic particles to partially dissolve the surfaces of the ceramic particles.

Taking zinc oxide ceramic particles as an example, the use of acetic acid helps the dissolution of the zinc oxide particle surface, thereby generating zinc ions; and the precipitation of zinc ions is realized in the heating and heat preservation processes, and pressure is further applied to the base material in the step, so that the precipitation can be generated at gaps among particles or air holes, and the porosity of the base material can be reduced.

It should be noted that, during the heating and heat preservation processes, the crystal grains in the substrate, mainly ceramic crystal grains, can grow to a certain extent and can eliminate partial defects, thereby reducing the porosity of the substrate to a certain extent.

Specifically, after pretreatment, the porosity of the ceramic plastic composite substrate can be reduced by 2-30%, so that the density of the substrate can be improved.

In addition, as mentioned above, the use of the acetic acid solution enables the precipitate to be formed in the pores, so that the compactness of the ceramic plastic composite substrate can be improved at a lower temperature.

In addition, the average grain size of the grains in the pretreated substrate can be increased by 5-80%. It is noted that different ceramic raw materials are adopted, and the grain growth rates are different after pretreatment. The following table 1 shows the comparison of the variation of the ceramic grain size before and after pretreatment with different ceramic raw materials in different examples.

TABLE 1 comparison of grain size changes before and after pretreatment of each ceramic raw material

The grain size is measured by referring to ISO 13383-1-2012Fine ceramics (advanced ceramics, advanced technical ceramics) -Microstructured chromatography-Part 1.

As can be seen from table 1 above, after pretreatment, the crystal grain size of zinc oxide changes relatively greatly, the alumina changes relatively little, and the silica is relatively centered. Therefore, in practical application, corresponding ceramic raw materials can be selected according to actual requirements.

Step S30: after the pretreatment, the substrate is subjected to a copolymerization treatment, so that the ceramic particles in the substrate and the plastic are crosslinked together, thereby obtaining the housing 10.

As described above, in the present embodiment, the substrate 11 is a ceramic-plastic composite material, and after the substrate is obtained, the substrate needs to be further processed to crosslink and tightly bond the ceramic and the plastic in the substrate, so as to improve the bonding force between the ceramic and the plastic.

Specifically, after the pretreatment, the substrate is subjected to heat treatment, and is heated to a second temperature of 280-350 ℃ and then is subjected to heat preservation for 4-8 hours, wherein the second temperature specifically can be 280 ℃, 300 ℃, 310 ℃, 330 ℃, 350 ℃ and the like, and the heat preservation time can be 4 hours, 5 hours, 6 hours, 7 hours, 8 hours and the like, and is not specifically limited herein.

Specifically, when the substrate is actually subjected to copolymerization treatment, the substrate can be directly heated to the second temperature and then subjected to heat preservation, or the substrate can be heated in a graded heating manner according to a pre-designed temperature curve. In an application scene, a corresponding clamp jig can be adopted to support the base material to be placed in an oven, then the temperature is raised to 150 ℃ from room temperature through 0.5-1h, and the temperature is kept at 150 ℃ for 2-4h; further heating to 260 ℃ from 150 ℃ for 2-4h, and preserving heat at 260 ℃ for 2-4h; then the temperature is raised to the second temperature from 260 ℃ for 0.5 to 1 hour.

In the heating process, the plastic itself can be crosslinked and branch chain expanded, and can be crosslinked with the modified functional groups on the surface of the ceramic particles, so that the combination of the ceramic and the plastic is tighter.

It should be noted that, in the present embodiment, when the substrate is subjected to the heat treatment, especially during the heat preservation process at the second temperature, the average grain size of the grains in the substrate may further be increased by 3% to 20%, so that the microstructure of the formed matrix 11 is denser; at the same time, a certain compressive stress is generated in the base material, thereby further improving the strength and hardness of the base 11.

The hardness and strength data of the substrate A formed after the above pretreatment and copolymerization treatment and the substrate B obtained without the above pretreatment and copolymerization treatment at a thickness ranging from 0.5 to 2mm, respectively, are shown in Table 2 below.

TABLE 2 comparison of the Properties of the substrates obtained by the different methods of manufacture

Item	Extrusion force/N	Pencil hardness/H	Vickers hardness/HV
				Base A	700-1000	4-5	200-300
Base B	200-500	1-2	50-70

The method comprises the steps of testing extrusion force data of a base body by adopting an extrusion force tester, specifically placing the corresponding base body on an extrusion clamp, using a spherical compression-resistant pressure head with the diameter of 10mm, aligning the top end of the pressure head to the middle position of the base body, applying pressure to the base body at the compression speed of 5mm/min until the base body is broken, and recording a pressure peak value as the corresponding extrusion force data. The pencil hardness and the Vickers hardness of the matrix are respectively obtained by adopting a pencil hardness meter and a Vickers hardness meter and testing under the load of 1 kg.

As can be seen from table 2 above, the matrix a formed after the pretreatment and the copolymerization treatment has significant advantages in strength and hardness compared with the matrix B formed without the pretreatment and the copolymerization treatment. It is thus verified that the housing 10 or the base 11 obtained in the above-described manner of the present application has superior strength and hardness.

Further, referring to fig. 7 in combination, in one embodiment, after the substrate is copolymerized, the method for manufacturing the housing 10 may further include:

step S40: processing the shape of the base material to obtain a matrix 11;

wherein, the outline processing of the base material can comprise processing of the shape and the size of the base material, and processing of flatness, smoothness and the like.

Specifically, in this embodiment, a numerically controlled machine (CNC) process may be performed on the substrate obtained after the copolymerization process, specifically, a diamond PCD milling cutter may be selected according to the actual shape and size requirements, the spindle rotation speed may be controlled to 10000 to 25000rpm, and the single cutting amount may be controlled to 0.01 to 0.50mm.

After being processed by a numerical control machine tool, the base material can be further ground and polished. Specifically, five-axis grinding and polishing machines, 13.6B double-side grinders, sweep beam machines, or the like may be used for grinding and polishing.

When polishing, different polishing processes can be selected according to different requirements. In this embodiment, two processes of rough polishing and fine polishing may be sequentially employed. Wherein, the rough polishing can adopt at least one of a sweeping machine, a double-sided grinding machine and a five-axis polishing machine; the polishing disc can be at least one of pig hair, a buffing disc, damping cloth, a glue wire, a copper wire, a carpet or a composite material of pig hair and buffing; the polishing assistant can be selected from water-based diamond grinding liquid, oil-based diamond grinding liquid, etc., and the diamond liquid particle size can be 0.5-20um, and the concentration can be 1-30W%. The fine polishing can adopt one or two of a sweeping machine and a double-sided lapping machine; the polishing liquid shell is one of silicon oxide and cerium oxide, the granularity can be 50-500nm, and the concentration can be 5-45W%. The selection can be specifically performed according to actual requirements, and is not limited herein.

Step S50: a functional layer is formed on the base 11.

The functional layer may be a light-shielding layer for shielding light, a color layer having a certain color, a texture layer exhibiting a texture effect, a reflective layer reflecting incident light to exhibit a certain gloss, or the like.

In this embodiment, the functional layer may be a hardened layer 12 having a certain hardness to protect the case 10 and an anti-fingerprint layer 13 having an anti-fingerprint function.

Specifically, the hardened layer 12 may be formed on the surface of the substrate 11 by sputtering, vacuum plating, evaporation plating, or the like. The material selected for forming the hardened layer 12 may be at least one of graphite, alumina, zirconia, silica, chromium nitride, and titanium nitride. The thickness of the hardened layer 12 may be 500-3000nm, such as 500nm, 1000nm, 2000nm, 3000nm, etc.

Further, after the hardened layer 12 is formed, an anti-fingerprint layer 13 may be further formed on the hardened layer 12, specifically, by coating, evaporation plating, and the like, which is not limited herein.

The above embodiments of the present application will be described below visually based on specific examples and comparative examples.

Example 1

The ceramic powder raw material selects spherical nano zinc oxide and alumina ceramic powder, wherein the particle size of the zinc oxide powder is 100-150 nm, and the particle size of the alumina powder is 100-200nm. Dissolving 10kg of nano alumina powder and 1kg of nano zinc oxide in 20wt% of 1mol/L acetic acid solution, performing ball milling treatment for 8 hours, and filtering and drying to obtain the ceramic powder to be treated.

Mixing 5kg of ceramic powder to be treated, 1% of modifier silane coupling agent, 0.5% of dispersant PVA and 2% of black pigment carbon black to obtain a mixture, adding water and alumina balls into the mixture according to the mass ratio of the mixture, water and grinding balls being 1.

And carrying out spray drying granulation on the prepared ceramic powder slurry in a granulation tower to obtain the ceramic powder. Wherein the feeding temperature is 80 ℃, the air inlet temperature is 150 ℃, the air exhaust temperature is 80 ℃, the temperature in the tower is 85 ℃, and the negative pressure in the tower is 100Pa.

And mixing and batching the ceramic powder prepared by granulation and the compound of PPS and PPSU according to the mass ratio of the ceramic powder to the plastic of 1.

And drying the prepared feed at the temperature of 120 ℃ for 12h, and then adding the feed into an injection machine for injection molding, wherein the molding temperature is 345 ℃, the injection speed is 90%, the injection pressure is 200MPa, the mold temperature is 145 ℃, and the pressure maintaining time is 30s, so that the ceramic plastic composite base material is prepared.

The prepared base material is placed in an acetic acid solution, the temperature is raised to 100 ℃ and kept for 3 hours, then a hot isostatic pressing device is adopted to pressurize to 150MPa of preset pressure, and high-pressure heating treatment is carried out, so that ceramic particles in the base material and the acetic acid solution generate certain chemical reaction, the base material is pretreated, after pretreatment, the crystal grains in the base material grow up by 20%, and the porosity is reduced by 20%.

After the pretreatment, the base material is supported by a corresponding clamping jig and placed in a drying oven, and the temperature rise copolymerization is carried out according to the following curve: (1) raising the temperature to 150 ℃ at room temperature over 1 hour; (2) keeping the temperature at 150 ℃ for 2h; (3) heating to 260 ℃ at 150 ℃ for 2h, and (4) keeping the temperature at 260 ℃ for 4h; (5) Heating to a second temperature of 310 ℃ at 260 ℃ for 0.5h, and keeping the temperature for 8h; (6) Naturally cooling to room temperature from 310 ℃, thereby realizing the copolymerization between the plastic and the ceramic in the substrate, and further growing 15% of crystal grains after the copolymerization.

And performing CNC (computer numerical control) processing on the product obtained after the copolymerization treatment according to the pre-designed shape and size, specifically selecting a diamond PCD milling cutter, controlling the rotating speed of a main shaft at 22000rpm, and controlling the single cutting amount to be 0.05mm.

And after CNC machining, further carrying out rough polishing and fine polishing treatment on the base material in sequence to obtain the base body of the shell. Wherein, the rough polishing adopts a sweeping machine, a polishing disc is made of a composite material of pig hair and ground skin, a polishing auxiliary agent adopts water-based diamond grinding fluid, the granularity is 2um, and the concentration is 10W%; the fine polishing adopts a sweeping machine, and the polishing solution adopts silicon oxide, the granularity is 200nm, and the concentration is 40W%.

After the above treatment, a substrate having a thickness of 0.8mm was obtained, which had a pencil hardness of 5H under a load of 1kg, an extrusion force of 800N measured by an extrusion force tester, and a porosity of 0.02%. The test modes of pencil hardness and extrusion force are the same as the test modes; the porosity test method refers to GB-T25995-2010 fine ceramic density and apparent porosity test method.

After polishing, a hardened layer is further plated on the surface of the obtained substrate in a sputtering vacuum plating mode, wherein the hardened layer is made of aluminum oxide and has the thickness of 1um. After the hardened layer is formed, an anti-fingerprint layer is further plated on the hardened layer.

Example 2

The ceramic powder raw material adopts spherical nano zinc oxide and silicon oxide ceramic powder, wherein the particle size of the zinc oxide powder is 100-150 nm, and the particle size of the silicon oxide powder is 100-200nm. 10kg of nano silicon oxide powder and 1kg of nano zinc oxide are dissolved in 20wt% of 1mol/L acetic acid solution, ball milling treatment is carried out for 8 hours, and then filtering and drying are carried out to obtain the ceramic powder to be treated.

And carrying out spray drying granulation on the prepared ceramic powder slurry in a granulation tower to obtain the ceramic powder. Wherein the feeding temperature is 80 ℃, the air inlet temperature is 150 ℃, the air outlet temperature is 80 ℃, the temperature in the tower is 85 ℃, and the negative pressure in the tower is 100Pa.

The prepared base material is placed in an acetic acid solution, the temperature is raised to 110 ℃ and kept for 4h, then hot isostatic pressing equipment is adopted to pressurize to 180MPa of preset pressure, and high-pressure heating treatment is carried out, so that certain chemical reaction is carried out between ceramic particles in the base material and the acetic acid solution, the base material is pretreated, after pretreatment, the crystal grains in the base material grow up by 15%, and the porosity is reduced by 18%.

After the pretreatment, the base material is supported by a corresponding clamping jig and placed in a drying oven, and the temperature rise copolymerization is carried out according to the following curve: (1) raising the temperature to 150 ℃ at room temperature over 1 hour; (2) keeping the temperature at 150 ℃ for 2h; (3) heating to 260 ℃ at 150 ℃ for 2h, and (4) keeping the temperature at 260 ℃ for 4h; (5) Heating to a second temperature of 320 ℃ at 260 ℃ for 0.5h, and preserving heat for 8h; (6) Naturally cooling from 320 ℃ to room temperature, thereby realizing the copolymerization between the plastic and the ceramic in the substrate, and further growing up 20 percent of crystal grains after the copolymerization.

And after CNC machining, further carrying out rough polishing and fine polishing treatment on the base material in sequence to obtain the matrix of the shell. Wherein, the rough polishing adopts a sweeping machine, a polishing disc is made of a composite material of pig hair and ground skin, a polishing auxiliary agent adopts water-based diamond grinding fluid, the granularity is 2um, and the concentration is 10W%; the fine polishing adopts a sweeping machine, and the polishing solution adopts silicon oxide, the granularity is 200nm, and the concentration is 40W%.

After the above treatment, a substrate having a thickness of 0.8mm was obtained, which had a pencil hardness of 4H under a load of 1kg, a pressing force of 920N measured by a pressing force tester, and a porosity of 0.01%. The test modes of pencil hardness and extrusion force are the same as the test modes; the porosity test method refers to GB-T25995-2010 Fine ceramics Density and apparent porosity test method.

After polishing, a hardened layer is further plated on the surface of the obtained substrate in a sputtering vacuum plating mode, wherein the hardened layer is made of aluminum oxide and is 1um thick. After the hardened layer is formed, an anti-fingerprint layer is further plated on the hardened layer.

Example 3

The ceramic powder raw material adopts spherical nano zinc oxide and silicon oxide ceramic powder, wherein the particle size of the zinc oxide powder is 100nm-150nm, and the particle size of the silicon oxide powder is 100-200nm. 10kg of nano silicon oxide powder and 1kg of nano zinc oxide are dissolved in 20wt% of 1mol/L acetic acid solution, ball-milling treatment is carried out for 8 hours, and then filtering and drying are carried out to obtain the ceramic powder to be treated.

The prepared base material is placed in an acetic acid solution, the temperature is raised to 120 ℃ at the first temperature and is kept for 10 hours, then hot isostatic pressing equipment is adopted to pressurize to 180MPa at preset pressure, and high-pressure heating treatment is carried out, so that ceramic particles in the base material and the acetic acid solution generate certain chemical reaction, the base material is pretreated, after pretreatment, crystal grains in the base material grow up by 3%, and the porosity is reduced by 5%.

After the pretreatment, the base material is supported by a corresponding clamping jig and placed in a drying oven, and the temperature rise copolymerization is carried out according to the following curve: (1) raising the temperature to 150 ℃ at room temperature over 1 hour; (2) keeping the temperature at 150 ℃ for 2h; (3) heating to 260 ℃ at 150 ℃ for 2h, and (4) keeping the temperature at 260 ℃ for 4h; (5) Raising the temperature to a second temperature of 330 ℃ after 0.5h at 260 ℃ and preserving the temperature for 8h; (6) Naturally cooling from 330 ℃ to room temperature, thereby realizing the copolymerization between the plastic and the ceramic in the substrate, and further growing up 5 percent of crystal grains after the copolymerization.

After the above treatment, a substrate having a thickness of 0.8mm was obtained, which had a pencil hardness of 4H under a load of 1kg, a pressing force of 655N as measured by a pressing force tester, and a porosity of 0.08%. The test modes of pencil hardness and extrusion force are the same as the test modes described above; the porosity test method refers to GB-T25995-2010 fine ceramic density and apparent porosity test method.

Comparative example

The ceramic powder raw material adopts spherical nano zinc oxide and silicon oxide ceramic powder, wherein the particle size of the zinc oxide powder is 100-150 nm, and the particle size of the silicon oxide powder is 100-200nm. Dissolving 10kg of nano silicon oxide powder and 1kg of nano zinc oxide in water, carrying out ball milling treatment for 8 hours, and then filtering and drying to obtain the ceramic powder to be treated.

CNC machining is carried out on the obtained base material according to the pre-designed shape and size, specifically, a diamond PCD milling cutter is selected, the rotating speed of a spindle is controlled at 22000rpm, and the single cutting amount is 0.05mm.

And after CNC machining, further carrying out rough polishing and fine polishing treatment on the base material in sequence to obtain the base body of the shell. Wherein, the rough polishing adopts a sweeping machine, the polishing disc is made of a pig hair and buffing composite material, the polishing auxiliary agent adopts water-based diamond grinding fluid, the granularity is 2um, and the concentration is 10W%; the fine polishing adopts a sweeping machine, and the polishing solution adopts silicon oxide, the granularity is 200nm, and the concentration is 40W%.

After the above treatment, a base having a thickness of 0.8mm was obtained, which had a pencil hardness of 2H under a load of 1kg, a pressing force of 400N measured by a pressing force tester, and a porosity of 0.9%. The test modes of pencil hardness and extrusion force are the same as the test modes; the porosity test method refers to GB-T25995-2010 Fine ceramics Density and apparent porosity test method.

The process parameters in the same process steps in the examples and comparative examples are substantially the same, and the main differences are shown in table 3 below.

TABLE 3 comparison of the main parameters in the examples and comparative examples

As can be seen from table 3 above, only the porosity of the substrate obtained in examples 1, 2 and 3 is lower by the method for manufacturing the casing according to the above embodiment of the present application, so that the structure is denser, and the data of the hardness and the extrusion force of the pencil with the same thickness are higher, which indicates that the hardness and the strength are higher, so that the casing has good performance. The matrix which is not manufactured by the shell manufacturing method has high porosity, so that the structure is not compact enough, the hardness and the strength of the matrix are relatively low, the scratch resistance of the corresponding shell is weak, the shell is easy to crack when being impacted by external force, and the requirement of a user on the performance of the shell is difficult to meet. Compared with the embodiments 1, 2 and 3, the main difference of the comparative example lies in that the acetic acid solution is not soaked in the early treatment stage, and the pretreatment and the copolymerization treatment are not carried out, so that the density, the hardness and the strength of the base body of the shell can be improved by carrying out the corresponding pretreatment and the copolymerization treatment on the base material in the shell manufacturing method, the shell manufactured by using the base material has strong wear resistance and scratch resistance, the risk of the shell falling and breaking is reduced, and the use requirement of a user is met.

The above embodiments are merely examples and are not intended to limit the scope of the present disclosure, and all modifications, equivalents, and flow charts using the contents of the specification and drawings of the present disclosure or those directly or indirectly applied to other related technical fields are intended to be included in the scope of the present disclosure.

Claims

1. A method of making a housing, comprising:

obtaining a ceramic plastic composite substrate;

pretreating the substrate to reduce the porosity of the substrate to a preset porosity;

and after the pretreatment, carrying out copolymerization treatment on the base material so as to enable the ceramic particles in the base material to be crosslinked with the plastic, thereby obtaining the shell.

2. The method of claim 1, wherein the step of pre-treating the substrate comprises:

placing the substrate in an acetic acid solution;

heating and pressurizing the substrate, keeping the temperature after heating to a first temperature, and maintaining the pressure after pressurizing to a preset pressure;

wherein, after pretreatment, the average grain size of the base material is increased by 5-80%, and the porosity is reduced by 2-30%.

3. The method according to claim 2, wherein the first temperature is 70-110 ℃, the holding time is 0.5-12h, the predetermined pressure is 120-180Mpa, and the holding time is 0.5-12h.

4. The method of claim 1, wherein the step of obtaining a ceramic-plastic composite substrate comprises:

obtaining ceramic powder infiltrated by an acetic acid solution;

mixing the ceramic powder with plastic cement and preparing a feed;

and forming the feedstock to obtain the substrate.

5. The method of claim 4, wherein the step of obtaining the ceramic powder infiltrated with the acetic acid solution comprises:

mixing a ceramic powder raw material with an acetic acid solution, and performing ball milling treatment to obtain ceramic powder to be treated;

modifying the ceramic powder to be treated to obtain ceramic powder slurry;

and granulating the ceramic powder slurry to obtain the ceramic powder.

6. The method of claim 1, wherein the step of subjecting the substrate to a copolymerization treatment comprises:

after the pretreatment, the base material is subjected to heating treatment, and is heated to a second temperature and then is subjected to heat preservation, so that the ceramic particles in the base material are crosslinked with the plastic, and the average grain size of the base material is increased by 3-20%.

7. The method of claim 6, wherein the second temperature is 280-350 ℃ and the holding time is 4-8 hours.

8. The method of claim 1, further comprising, after the copolymerizing the substrate:

carrying out appearance processing on the base material to obtain a matrix;

and forming a functional layer on the substrate.

9. A shell is characterized by comprising a base body, wherein the base body is made of a ceramic plastic composite material;

wherein the porosity of the matrix is not greater than 0.5%.

10. The casing of claim 9, wherein the matrix satisfies at least one of a dielectric constant of 4 to 8, an average crystal grain size of 50 to 1000nm, a pencil hardness of 4 to 9H under a 1kg load, and a pressing force of 200 to 1000N at a thickness of 1 mm.

11. The housing of claim 9, wherein the ceramic of the ceramic plastic composite material comprises at least one of zinc oxide, zirconium oxide, aluminum oxide, silicon oxide, titanium oxide, and silicon carbide; the plastic is at least one of polyphenylene sulfide, polyphenylene sulfone resin, polyamide and ethylene-vinyl acetate copolymer.

12. The housing of claim 9, further comprising at least one of a stiffening layer and an anti-fingerprint layer on the substrate.

13. An electronic device, comprising:

a housing defining an accommodating space;

the functional device is accommodated in the accommodating space;

wherein the shell is made by the method of any one of claims 1 to 8, or the shell of any one of claims 9 to 12.