WO2015010648A1

WO2015010648A1 - Metal-plastic composite and method for manufacturing the same

Info

Publication number: WO2015010648A1
Application number: PCT/CN2014/082977
Authority: WO
Inventors: Liang Liu
Original assignee: Shenzhen Byd Auto R&D Company Limited; Byd Company Limited
Priority date: 2013-07-25
Filing date: 2014-07-25
Publication date: 2015-01-29
Also published as: CN104339675A

Abstract

A method for manufacturing a metal-plastic composite and a metal-plastic composite are provided. The method comprises steps of: integrally forming a metal frame structure, wherein the metal frame structure comprises a metal frame, and a connecting terminal integrally formed between any two adjacent sides of the metal frame; performing an injection molding on an inner surface of the metal frame structure; anodizing the metal frame structure; milling off an injection molding plastic covering the connecting terminals; and removing the connecting terminals by milling to obtain the metal-plastic composite.

Description

METAL-PLASTIC COMPOSITE AND METHOD FOR MANUFACTURING THE SAME

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and benefits of Chinese Patent Application Serial No. 201310314359.1, filed with the State Intellectual Property Office of P. R. China on July 25, 2013, the entire content of which is incorporated herein by reference.

FIELD

The present disclosure relates to a metal-plastic integrally molding field, and more particularly to a method for manufacturing a metal-plastic composite, and a metal-plastic composite manufactured by the same.

BACKGROUND

Currently, light metal articles, especially aluminum alloy articles, are used widely in portable electronic devices.

For example, the aluminum alloy article is applied as the shell frame of the mobile phone. The shell frame includes four aluminum alloy sides with injection molding plastic disposed inside thereof. In order to improve the appearance texture of the shell frame of the mobile phone, the surface of the four aluminum alloy sides are usually treated with anodizing. A conventional method includes the steps of: (1) forming four separate aluminum alloy sides respectively; (2) performing a PMH (Plastic Metal Hybrid) injection molding to the four separate aluminum alloy sides; (3) anodizing and coloring the four separate aluminum alloy sides; and (4) assembling the four aluminum alloy sides to form a shell frame of a mobile phone.

However, the shell frame of the mobile phone manufactured by such conventional method may have disadvantages of color aberration between the four aluminum alloy sides. In addition, failing to anodize is usually caused during the anodizing process, thus resulting in a low product yield.

SUMMARY

Embodiments of the present disclosure seek to solve at least one of the problems existing in the prior art to at least some extent. According to a first aspect of the present disclosure, a method for manufacturing a metal-plastic composite is provided. The method includes steps of: integrally forming a metal frame structure, in which the metal frame structure includes a metal frame, and a connecting terminal integrally formed between any two adjacent metal sides of the metal frame; performing an injection molding on an inner surface of the metal frame structure; anodizing the metal frame structure; milling off an injection molding plastic covering the connecting terminals; and removing the connecting terminals by milling to obtain the metal-plastic composite.

In some embodiments, the injection molding plastic covering the connecting terminals is milled off by a T-type milling cutter.

In some embodiments, the metal frame includes four sides.

In some embodiments, the metal frame is made of aluminum.

In some embodiments, the metal frame is made of aluminum alloy.

In some embodiments, the metal frame is made of magnesium.

In some embodiments, the metal frame is made of magnesium alloy.

In some embodiments, the metal frame structure is integrally formed by CNC.

In some embodiments, the metal frame structure is integrally formed by first forging and then CNC.

In some embodiments, an injection molding plastic used in the injection molding includes polyphenylene sulfide.

In some embodiments, the injection molding plastic used in the injection molding further includes a fiberglass.

In some embodiments, a temperature of the injection molding ranges from 270 ^°C to 320 ^°C .

In some embodiments, a thickness of the injection molding plastic covering the connecting terminals ranges from 0.3mm to 0.5mm.

In some embodiments, anodizing the metal frame structure includes: immersing the metal frame and a nipper plate in an electrolyte solution, in which the metal frame acts as an anode and the nipper plate acts as a cathode; and applying a current to form an oxide layer on the metal frame.

In some embodiments, a diameter of the T-shaped cutter diameter ranges from 5mm to 10mm.

With the method for producing a metal-plastic composite according to embodiments of the present disclosure, by integrally forming the metal frame structure, the metal frame structure may be anodized by a single anodizing process, that is, all sides of the metal frame may be colored with the single anodizing process, which may prevent a color aberration and reduce a manufacture cost. Furthermore, the integrally formed metal frame structure may be conductively connected with an electrode contact of a small size, which may greatly reduce a possibility of failing to anodize during the anodizing process, thus improving a product yield. In addition, the anodizing process is performed only once in this method, thus significantly simplifying a manufacture process.

According to a second aspect of the present disclosure, a metal-plastic composite manufactured by the method for manufacturing a metal-plastic composite according to the first aspect of the present disclosure is provided.

In some embodiments, the metal-plastic composite is used as a shell frame of a mobile phone.

With the metal-plastic composite according to embodiments of the present disclosure, by integrally forming the metal frame structure, the metal frame structure may be anodized by a single anodizing process, that is, all sides of the metal frame may be colored with the single anodizing process. Therefore, a color aberration between respective side of the metal frame is reduced, and a manufacture cost of the metal-plastic composite is lowered. Furthermore, the integrally formed metal frame structure may be conductively connected with an electrode contact of a small size, which may greatly reduce a possibility of failing to anodize during the anodizing process, thus improving a product yield.

Additional aspects and advantages of embodiments of present disclosure will be given in part in the following descriptions, become apparent in part from the following descriptions, or be learned from the practice of the embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of the disclosure will become apparent and more readily appreciated from the following descriptions taken in conjunction with the drawings in which:

Fig. 1 is a partial structural schematic view of a metal frame and a connecting terminal obtained by step S I of a method for manufacturing a metal-plastic composite according to an embodiment of the present disclosure;

Fig. 2 is a partial structural schematic view of a structure obtained by step S2 of the method for manufacturing a metal-plastic composite according to an embodiment of present disclosure;

Fig. 3 is a schematic view shows milling of the structure obtained by step S4 of the method for manufacturing a metal-plastic composite according to an embodiment of present disclosure;

Fig. 4 is a schematic partial enlarged view of a part A in Fig.3; and

Fig. 5 is a schematic partial enlarged view of a shell frame of a mobile phone according to an embodiment of the present disclosure. DETAILED DESCRIPTION

Reference will be made in detail to embodiments of the present disclosure. The embodiments described herein are explanatory, illustrative, and used to generally understand the present disclosure. The embodiments shall not be construed to limit the present disclosure.

The inventors of the present disclosure find that main reasons for a conventional method for manufacturing a metal-plastic composite having disadvantages of color aberration between different metal sides and an occurring of failing to anodize during an anodizing process lie in following facts. In order to obtain a good antenna performance, a plurality of aluminum alloy sides of the metal frame described in the BACKGROUND need to be separated. In an anodizing step, each separated aluminum alloy side should be conductively connected with an electrode contact by a fixture. However, it is difficult for each separated aluminum alloy side to be conductively connected with the electrode contact due to some external factors such as a non-stability of the fixture, a flow impulsion in an electrolyte solution and an unfavorable force at the electrode contact, which may cause the color aberration between different metal sides and an occurring of failing to anodize during the anodizing process.

In order to solve at least one of the problems described above, according to a first aspect of the present disclosure, a method for manufacturing a metal-plastic composite is provided. The method includes following steps.

At step S I, a metal frame structure is integrally formed, in which the metal frame structure includes a metal frame, and a connecting terminal integrally formed between any two adjacent metal sides of the metal frame.

In some embodiments, the metal frame structure may be made of aluminum, aluminum alloy, magnesium or magnesium alloy

The metal frame structure may be integrally formed by various common methods, such as directly by CNC (Computer Numerical Control) or by first forgoing and then CNC.

In some embodiments, the method may be used for manufacturing a shell frame of a mobile phone. The metal frame structure may have a quadrangle shape and include four metal sides and four connecting terminals. Each connecting terminal is integrally formed between two adjacent metal sides. Alternatively, the method may be used for manufacturing other metal-plastic composite, for example, a shell frame of a 3C (Computer-Communication-Consumer) electronic device. In this case, the shape of the metal frame structure is depended on actual requirements.

At step S2, an injection molding is performed to an inner surface of the metal frame structure.

The injection molding may refer to PMH injection molding, which is well known to the person skilled in the art and will not be described in details herein. In one embodiment, an injection molding plastic used in the injection molding may include but not limited to polyphenylene sulfide (PPS). In another embodiment, the injection molding plastic may further include a fiberglass to enhance a strength of the injection molding plastic. In some embodiments, a temperature of the injection molding ranges from about 270 ^°C to about 320 ^°C .

In some embodiments, a thickness of the injection molding plastic covering the connecting terminals is not particularly defined, and is depended on actual requirements. However, the thickness of the injection molding plastic covering the connecting terminals should not be too large, otherwise it will increase a time for a subsequent milling process. In some embodiments, the thickness of the injection molding plastic covering the connecting terminals may range from about 0.3mm to about 0.5mm.

At step S3, the metal frame structure is anodized.

The anodizing process is well known to the person skilled in the art. In one embodiment, the anodizing process may include: immersing the metal frame and a nipper plate in an electrolyte solution, in which the metal frame acts as an anode and the nipper plate acts as a cathode; and applying a current to form an oxide layer on the metal frame. By the anodizing process, the metal frame structure may meet different requirements of an appearance texture. Since the metal frame structure is integrally formed, that is, the connecting terminals and the metal frame are integrally formed, on one hand, the electrode contacts may be reduced, on the other hand, the flow impulsion in the electrolyte solution may be resisted, and thus the anodizing may be performed in stability so as to prevent the color aberration between different metal sides. Furthermore, the integrally formed metal frame structure may be conductively connected with an electrode contact of a small size, which may greatly reduce a possibility of failing to anodize during the anodizing process, thus improving a product yield. In addition, the anodizing process is performed only once in this method, thus significantly simplifying a manufacture process.

At step S4, an injection molding plastic covering the connecting terminals are milled off, and the connecting terminals are further removed by milling to obtain the metal-plastic composite.

The main purpose of the milling process is to separate the metal frames from the connecting terminals so as to meet performance requirements. In some embodiments, the milling process includes: milling off the injection molding plastic covering the connecting terminals and then milling off the connection terminals to disconnect the metal frames from each other. After the milling process, a metal-plastic composite is obtained.

In some embodiments, the milling process is performed by a T-type milling cutter. In some embodiments, a diameter of the T-shaped cutter diameter may be, but not limited to, about 5mm ~ 10mm.

With the method for producing a metal-plastic composite according to an embodiment of the present disclosure, by integrally forming the metal frame structure, the metal frame structure may be anodized by a single anodizing process, that is, all sides of the metal frame may be colored with the single anodizing process, which may prevent a color aberration and reduce a manufacture cost. Furthermore, the integrally formed metal frame structure may be conductively connected with an electrode contact of a small size, which may greatly reduce a possibility of failing to anodize during the anodizing process, thus improving a product yield. In addition, the anodizing process is performed only once in this method, thus significantly simplifying a manufacture process.

Two explanatory examples will be described below to further understand the present disclosure, which shall not be construed to limit the present disclosure.

Example 1

The method is used for manufacturing a shell frame of a mobile phone in this example. The method includes following steps. At step S 11, a square shaped metal frame structure is integrally formed by first forging and then CNC. The metal frame structure includes a first metal side 1, a second metal side 2, a third metal side 3, and a fourth metal side 4, and a connecting terminal integrally formed between each two adjacent metal sides (only a first connecting terminal 12 integrally formed between the first metal side 1 and the second metal side 2 is shown in Fig. 1).

At step S 12, a PMH injection molding is performed to an inner surface of the metal frame structure. A coverage area of the PMH injection molding plastic 5 is shown in Fig. 2. As shown in Fig. 5, a gap between any two adjacent metal sides is filled with the PMH injection molding plastic 5, and all connecting terminals are covered by the PMH injection molding plastic 5. In some embodiments, a thickness of the PMH injection molding plastic 5 covering the connecting terminal is about 0.3mm. A shape of the PMH injection molding plastic 5 is dependent on product requirement. In the embodiment, a temperature of the PMH injection molding ranges from about 270 ^°C to about 320 ^°C .

At step S 13, the metal frame structure is anodized. An anodizing process may include: immersing the metal frame and a nipper plate in an electrolyte solution, in which the metal frame acts as an anode and the nipper plate acts as a cathode; and applying a current to form an oxide layer on the metal frame.

At step S 14, as shown in Figs. 3-4, a T-type milling cutter 6 with a diameter of 6.0mm is placed in an intra-area of the metal frame structure, the T-type milling cutter 6 is activated to first mill off the PMH injection molding plastic 5 covering the connecting terminals and then mill off the connecting terminals, and thus a groove 7 as shown in Fig.5 is formed at a place where the connecting terminal is originally formed, such that two adjacent metal sides (such as the first side 1 and the second metal side 2 shown in Fig. 2) of the metal frame are disconnected from each other. By this way, the shell frame of the mobile phone is obtained.

At step S 15, above steps S ll to S 14 are repeated for 100 times to obtain 100 samples. The

100 samples are tested by visual observation to determine whether there is a color aberration between different metal sides and whether failing to anodize occurs, and if no, the sample is regarded as a good product. In this example, a product yield achieves 100%.

Example 2

The method is used for manufacturing a shell frame of a mobile phone in this example. The method includes following steps.

At step S21, a square shaped metal frame structure is integrally formed by first forging and then CNC. The metal frame structure includes a first metal side 1, a second metal side 2, a third metal side 3, and a fourth metal side 4, and a connecting terminal integrally formed between each two adjacent metal sides (only a first connecting terminal 12 integrally formed between the first metal side 1 and the second metal side 2 is shown in Fig. 1).

At step S22, a PMH injection molding is performed to an inner surface of the metal frame structure. A coverage area of the PMH injection molding plastic 5 is shown in Fig. 2. As shown in Fig. 5, a gap between any two adjacent metal sides is filled with the PMH injection molding plastic 5, and all connecting terminals are covered by the PMH injection molding plastic 5. In some embodiments, a thickness of the PMH injection molding plastic 5 covering the connecting terminal is about 0.5mm. A shape of the PMH injection molding plastic 5 is dependent on product requirement. In the embodiment, a temperature of the PMH injection molding ranges from about 270 ^°C to about 320 ^°C .

At step S23, the metal frame structure is anodized. An anodizing process may include: immersing the metal frame and a nipper plate in an electrolyte solution, in which the metal frame acts as an anode and the nipper plate acts as a cathode; and applying a current to form an oxide layer on the metal frame.

At step S24, as shown in Figs. 3-4, a T-type milling cutter 6 with a diameter of 6.5mm is placed in an intra-area of the metal frame structure, the T-type milling cutter 6 is activated to first mill off the PMH injection molding plastic 5 covering the connecting terminals and then mill off the connecting terminals, and thus a groove 7 as shown in Fig.5 is formed at a place where the connecting terminal is originally formed, such that two adjacent metal sides (such as the first side 1 and the second metal side 2 shown in Fig. 2) of the metal frame are disconnected from each other. By this way, the shell frame of the mobile phone is obtained.

At step S25, above steps S21 to S24 are repeated for 100 times to obtain 100 samples. The 100 samples are tested by visual observation to determine whether there is a color aberration between different metal sides and whether failing to anodize occurs, and if no, the sample is regarded as a good product. In this example, a product yield achieves 100%.

According to a second aspect of the present disclosure, a metal-plastic composite manufactured by the method for manufacturing a metal-plastic composite according to embodiments of the first aspect of the present disclosure is provided.

Although explanatory embodiments have been shown and described, it would be appreciated by those skilled in the art that the above embodiments cannot be construed to limit the present disclosure, and changes, alternatives, and modifications can be made in the embodiments without departing from spirit, principles and scope of the present disclosure.

Claims

WHAT IS CLAIMED IS:

1. A method for manufacturing a metal-plastic composite, comprising steps of:

integrally forming a metal frame structure, wherein the metal frame structure comprises a metal frame, and a connecting terminal integrally formed between any two adjacent sides of the metal frame;

performing an injection molding on an inner surface of the metal frame structure;

anodizing the metal frame structure;

milling off an injection molding plastic covering the connecting terminals; and

removing the connecting terminals by milling to obtain the metal-plastic composite.

2. The method according to claim 1, wherein the injection molding plastic covering the connecting terminals is milled off by a T-type milling cutter.

3. The method according to claim 1 or 2, wherein the metal frame comprises four sides.

4. The method according to any of claims 1-3, wherein the metal frame is made of aluminum.

5. The method according to any of claims 1-3, wherein the metal frame is made of aluminum alloy.

6. The method according to any of claims 1-3, wherein the metal frame is made of magnesium.

7. The method according to any of claims 1-3, wherein the metal frame is made of magnesium alloy.

8. The method according to any of claims 1-7, wherein the metal frame structure is integrally formed by CNC.

9. The method according to any of claims 1-7, wherein the metal frame structure is integrally formed by first forging and then CNC.

10. The method according to any of claims 1-9, wherein an injection molding plastic used in the injection molding comprises polyphenylene sulfide.

11. The method according to claim 10, wherein the injection molding plastic used in the injection molding further comprises a fiberglass.

12. The method according to any of claims 1-11, wherein a temperature of the injection molding ranges from 270 ^°C to 320 ^°C .

13. The method according to any of claims 1- 12, wherein a thickness of the injection molding plastic covering the connecting terminals ranges from 0.3mm to 0.5mm.

14. The method according to any of claims 1-13, wherein anodizing the metal frame structure comprises:

immersing the metal frame and a nipper plate in an electrolyte solution, wherein the metal frame acts as an anode and the nipper plate acts as a cathode; and

applying a current to form an oxide layer on the metal frame.

15. The method according to claim 2, wherein a diameter of the T-shaped cutter diameter ranges from 5mm to 10mm.

16. A metal-plastic composite manufactured by the method for manufacturing a metal-plastic composite according to any of claims 1-15.

17. The metal-plastic composite according to claim 16, wherein the metal-plastic composite is used as a shell frame of a mobile phone.