CN-122013275-A - Anodic oxidation reworking method after metal middle frame milling and breaking

Abstract

The invention discloses an anodic oxidation reworking method after a metal middle frame is broken, and belongs to the technical field of surface treatment of metal structural parts. According to the scheme, conductive adhesive is coated at two end points of a broken bridge of a middle frame product with an anodic oxidation appearance defect so as to connect two sides of the broken bridge, shielding adhesive is coated on the surface of the cured conductive adhesive, after the shielding adhesive is cured, an original anodic oxidation layer is removed, anodic oxidation treatment is carried out again to form a new anodic oxidation layer, and finally the shielding adhesive and the conductive adhesive are removed. The scheme adopts a combined process of conductive adhesive and shielding adhesive to replace the traditional titanium accessory connection method, accurately solves the problem of poor appearance of anodic oxidation reworking caused by electric bridge cutoff formed after the metal middle frame is turned on and off, and has the advantages of strong universality, low cost, high reliability, short development period and the like.

Inventors

• ZHAO JINGLONG
• YANG JUNJIAN
• WANG JIAJUN
• HE WEIDE
• YANG XINYU
• JIANG FU
• HU SHEN

Assignees

• 伯恩高新科技（惠州）有限公司
• 伯恩光学(深圳)有限公司

Dates

Publication Date

20260512

Application Date

20260106

Claims (7)

1. 1. The anodic oxidation reworking method after the metal middle frame is subjected to gong breaking, and an electrical broken bridge is formed after the metal middle frame is subjected to a nine-clamp gong breaking process, and the anodic oxidation reworking method is characterized by comprising the following steps of: Step S1, screening out a metal middle frame product with anodic oxidation appearance defects; Step S2, coating conductive adhesive on two end points of the broken bridge to form a conductive adhesive layer bridging the broken bridge, and curing the conductive adhesive layer; Step S3, spot-coating acid and alkali corrosion resistant shielding glue on the surface of the conductive glue layer to form a shielding glue layer covering the conductive glue layer, and curing the shielding glue layer; s4, removing the original anodic oxidation layer on the surface of the metal middle frame product; s5, carrying out anodic oxidation treatment on the metal middle frame product again to form a new anodic oxidation layer; and S6, removing the shielding adhesive layer and the conductive adhesive layer.
2. 2. The method for reworking the metal middle frame by anodic oxidation after milling according to claim 1, wherein in the step S2, the conductive adhesive is applied by an automatic adhesive dispensing device, the automatic adhesive dispensing device automatically identifies the bridge breaking position according to a milling structure drawing of the metal middle frame, and precisely dispenses the conductive adhesive at two ends of the bridge breaking.
3. 3. The method for reworking the metal middle frame according to claim 1, wherein in the step S2, the thickness of the conductive adhesive layer is 0.8 mm-1.2 mm.
4. 4. The method for reworking the metal center after being milled according to claim 1, wherein in the step S2, the conductivity of the conductive paste is not more than 0.1 Ω -cm.
5. 5. The method for reworking the metal middle frame after being milled according to claim 1, wherein the shielding glue is ultraviolet light curing glue, and the thickness of the shielding glue layer is 0.3 mm-0.5 mm.
6. 6. The method according to claim 1, wherein in step S6, the masking adhesive layer and the conductive adhesive layer are removed simultaneously by immersing the metal middle frame in a special degumming agent.
7. 7. The method for reworking the anodic oxidation process after the metal middle frame is milled according to claim 1, wherein in the step S1, a manual visual detection mode is adopted to screen the metal middle frame product with the appearance defects of the anode, wherein the appearance defects comprise no coloring, color difference and no local film layer of the anode.

Description

Anodic oxidation reworking method after metal middle frame milling and breaking Technical Field The invention relates to the technical field of surface treatment of metal structural parts, in particular to an anodic oxidation reworking method after a metal middle frame is broken. Background In the field of manufacturing precise structural members such as smart phones and tablet personal computers, metal middle frames such as aluminum alloy, titanium alloy and steel alloy are usually molded by adopting a CNC (computer numerical control) processing technology. The "nine-clamp gong-break" is a common machining mode, and is used for forming a preset breaking line on the periphery of the middle frame so as to facilitate subsequent separation or assembly. However, in the actual production process, the process is easy to cause the middle frame to be completely disconnected at the gong and break bridge in the electrical sense. When the appearance defect of anodic oxidation is found later and anodic oxidation is needed to be carried out, the anodic treatment depends on the overall conductivity of the workpiece to realize uniform coloring, and the broken bridge area cannot conduct electricity due to the loss of electric connection, so that the appearance defects of partial non-coloring, chromatic aberration and the like are caused, and the yield and delivery quality of the product are seriously affected. As shown in fig. 1, two light-colored vertical lines in the frame selection area are fracture lines formed by the gong-breaking process, and because of the existence of the two fracture lines, a local area in the middle of the fracture lines is not colored, and obvious appearance difference exists between the local area and other areas at the periphery of the middle frame. In order to solve the above problems, the reworking scheme of the titanium connecting fitting matched with the special hanger shown in fig. 2 is generally adopted in the prior art. The method comprises the steps of configuring a titanium fitting and a rubber plug which can be repeatedly used for a plurality of times, developing a special hanging tool aiming at the gong and breaking structures of middle frames of different machine types, and manually installing the titanium fitting at a bridge breaking position during the reworking process to enable a plurality of disconnected areas to be connected and conducted through the titanium fitting, fixing the position of an opening on the middle frame by utilizing the rubber plug, completing operations such as hanging up and hanging down by utilizing the special hanging tool, and enabling a workpiece to recover a conductive path in an anode tank, so that the anodic oxidation reworking is realized. However, this prior art has a number of significant drawbacks: (1) The versatility is poor. Because the gong and breaking positions, geometric shapes and customer structure requirements of the middle frames of different projects are greatly different, special hanging tools and titanium accessories are required to be independently designed and verified for each type of structure, and part of complex or high-precision structures cannot be even effectively adapted, so that defective appearance products can only be scrapped. (2) The reworking cost is high. Meanwhile, the assembly, disassembly and hanger operation of the titanium fittings are dependent on manual work, the time for hanging up and hanging down of a single product respectively reaches 120 seconds and 90 seconds, and the comprehensive reworking cost reaches 10.948 yuan/PCS. (3) The reworking yield is low. The defective rate after bridge cut-off reworking is still maintained to be more than 20% under the influence of factors such as assembly precision, contact reliability and the like, and the problem of conductive failure cannot be fundamentally solved. (4) The development period is long. The special hanger and the titanium fitting required by the new project need to undergo a plurality of links such as drawing design, exterior cooperation proofing, in-factory trial assembly, process verification and the like, the whole development period is usually more than one month, and the development rhythm of products such as mobile phones and the like which are iterated quickly is difficult to meet. (5) The consumable reliability is insufficient. The titanium accessory is easy to cause the problems of screw sliding, breakage and the like after being used for 3-4, and once the titanium accessory is broken in the anode groove, the titanium accessory is very likely to cause damage or scrapping of products. In summary, the existing reworking scheme based on titanium accessory connection has obvious bottlenecks in aspects of universality, cost, yield, period, reliability and the like, and a novel reworking technology which does not need a special hanger, does not depend on high-cost consumables and can efficiently and reliably recover a conductive path is needed. Discl