Aluminum board process-C

5.9.2 precautions:
A.by board member of the board must pay attention to check, for no good grinding can take to mill again, for chafed can pick out those with sand paper (2000 #), sand flat after grinding plate.    
B. in a discontinuous production condition, must strengthen the maintenance, to ensure clean, tank cleaning.   
5.9.3 must be confirmed by the captain after Aluminum circuiy board surface has been handle, can only flow down.   
5.10 impact
5.10.1 edge with both hands, pay attention to the aluminum surface protection.    
5.10.2 aluminum plate forming die adopts high-grade beer board, and punching and shape a rushed or separate, impact, in accordance with the requirements of the MI must be placed after a piece of white paper on the surface of the aluminum plate.
5.10.3 impact should strengthen the inspection, pay attention to the don't fall green oil and chafed board face.   
5.10.4 no washing board at the time of the final inspection, the board, board with board between every good white skin.
5.10.5 every flush plate factory mold with a brush to clean again. 
5.11 final inspection: according to the IPC comprehensive enterprise standard and so on for each test.   

5.12 the packing  
5.12.1 different period, different packaging material number plate should be classification.    
5.12.2 when packing, please put moistureproof paper insulation and bead, and in the smallest package labels model indicating the version number, after the production cycle () a month for a cycle, etc.
6. About the final inspection chafed, oxidation of aluminum board's final inspection rework method caused by in the process of production of oxidation and flower aluminum plate, rework processing as follows.    
6.1 aluminum surface oxidation of aluminum plate: first line up the aluminum plate and emissions in the desktop, the cover line with welan and compaction, and then a few welan with double-sided adhesive, with a piece of light copper stick on it, the same to compaction, and then you can get a deburring machine on grinding plate.Note that before the grinding plate must turn off the pickling and put this section of the road wheel with tap water rinse clean to prevent pollution of acid tin, or directly from pickling after washing section into the aluminum base face up, only to open the above grinding brush, after grinding plate, such as oxidation phenomenon, can be ground again.Good grinding plate monolithic monolithic, put in grinding machine drying on the drying period, place 5 ~ 10 min, also can be put on the tray in white paper, take to the oven drying, 100 ℃ by 5 ~ 10 min, be careful not to take to forming washing machine to dry, because of its low temperature, it will bring aluminum surface oxidation.  

6.2 aluminum surface brush flower aluminum plate:
6.2.1 aluminum surface slightly brush flower aluminum plate, according to the aluminum surface oxidation 6.1 rework method.
6.2.2 aluminum face serious chafed aluminum board, first of all, use 2000 # sandpaper will wipe brush flat take place, and then use 4000 # sandpaper gently brush again, then 6.2.1 aluminum surface oxidation of aluminum plate rework method for processing.

Aluminum PCB board Application

Led aluminum board thermal conductivity
Led aluminum pcb board and thermal conductivity aluminum board in the middle of the insulating layer (generally is PP, now has a thermal conductive adhesive, etc.), it is one of the three major measure of aluminum plate quality, heat resistance and pressure value is another two performance).Aluminum plate thermal conductivity can be tested after plate bonding instrument tests data, the high value of thermal conductivity is generally ceramic, copper, etc., but due to the cost into consideration, is currently on the market mainstream electronic aluminum plate, aluminum plate thermal conductivity of the corresponding is parameters of people's concern, the higher the coefficient of thermal conductivity is one of the symbols of the better performance.

Led aluminum plate classification
Led fluorescent lamp aluminum plate is aluminum plate classification, street light aluminum plate, tube light aluminum plate, wall lamp aluminum plate, shoot the aluminum plate, energy-saving light aluminum plate, electrodeless lamp aluminum plate, aluminum board, ceiling aluminum plate, wash wall lamp aluminum plate, the ball bubble lamp aluminum plate, tunnel light aluminum plate, floodlight, aluminum plate, aluminum plate, wall lamp high-power aluminum plate, small power aluminum plate, guardrail tube aluminum plate, neon lights aluminum plate, corn lamp aluminum plate, the candle light aluminum plate, absorb dome light aluminum plate, kitchen lamp aluminum plate, corridor lights aluminum plate, buried lights aluminum plate, dared light aluminum plate, industrial and mining lamp aluminum plate, aluminum plate bridge lights, floor tile lamp aluminum plate, stair light aluminum plate.

LED aluminum plate insulating layer
LED aluminum plate insulation layer is one of the most core technology of aluminum plate, the main adhesive, insulation and thermal conductivity of the function.Aluminum base board insulation is a power module.
Structure of the largest thermal barrier.Insulation heat conduction performance, the better, the more conducive to the spread of the heat produced during the operation, will be conducive to reduce the operating temperature of the device, so as to improve the module of power load, reducing the volume and prolong life, improve the power output, etc.
LED aluminum plate
1, audio equipment: input, output amplifier, balanced amplifier, audio amplifier, preamplifier, power amplifier, etc.   
2, power equipment, switching regulator ` DC/AC converter ` SW regulator, etc.   
3, communication electronic equipment: high frequency increase ` filtering electrical ` transmitting circuit.   
4, office automation equipment, motor drives, etc.    
5, automobile, electronic regulator ` igniter ` power controller, etc.   
6, a computer: CPU board ` diskette drive ` power supply device, etc.   
7, power module, inverter ` solid relay ` rectifier bridge, etc

Repairing printed circuit boards - tips by Exception PCB

PCBs, or printed circuit boards, have revolutionised the electronic industry; however they lack the robustness of the earlier, steel-chassis, hardwired equipment, driving them to be much easier to crack. Restoring a circuit board needs a particular level of analytical ability, along with the skill to handle each element in the correct way.

Without having a thorough knowledge of the way a circuit board works, experts from Exception PCB express that diagnosing the trouble will be a problem. For PCBs that are especially complex, you might also need an oscilloscope to discover signals at different points, so as to discover the section which is creating the problem. Once this component has been discovered, it will then have to be replaced. Here, Exception PCB provides you with a brief guide on how to do this.

As outlined by Exception PCB, with the majority of passive (and occasionally active) components, a similar, as opposed to an exact copy of the broken element can be used as a replacement. You will find, for example, several unique versions of voltage regulators available, and one version can easily be swapped for another in a PCB. However, broken active components that have a very specific function (for example, audio amplifier chips) must be replaced with an exact copy.

After you have acquired the right replacement, you'll have to place the PCB on a flat surface for the fix. Exception PCB says that you might use tape to stick the board on both sides to the surface, to ensure that it doesn't move whilst you are carrying out the replacement. Pull the damaged component off the board very delicately, using tweezers. Next, switch on your soldering iron and set it to about 400 degrees Celsius.

Take some copper wire and put it on the pads of the PCB where the component was, and use the soldering iron to heat it. Wonderful pcb that any surplus solder remaining on these pads could be absorbed by the copper. Get in line the leads of the replacement component with the board's pads, taking a look at to make sure that the element is aligned as it needs to be. Then, use the soldering iron and the solder to join the leads with the corresponding pads on the board. 

Electroless Copper Plating

Metallization is required on the wall of the drill holes to make them conductive. It can be done by chemical deposition or direct metallization. For double layer boards, chemical deposition is common. It is an electroless process because the deposition of copper is done in the absence of electrical current. The objective of the electroless copper plating process is to deposit a very thin layer of copper over the entire surface of the copper cladding and on bare hole walls. This layer should be thick enough to allow the electrical current during the subsequent electrolytic plating. Normally, a thickness of 0.001 Mil to 0.0025 Mil is acceptable for further electroplating at low start current. The thickness of the PTH will be increased to the required level after the electrolytic copper plating.

Several proprietary solutions are available for making electroless copper. Basically, a precious metal palladium is being used as an activator to provide a site for the adhesion of electroless copper. Electroless copper bath contains an alkaline chelated copper reducing solution that deposits thin layer of copper on activated surface.
The thickness of electroless copper needed can be observed from the following table which gives the thickness of copper foil on Aluminum pcb. For reliable operation, PTH wall thickness should be around 0.7 Mil to 1 Mil.

Electroless copper plating process is consists of 4 baths; acid predip bath, activator bath, postactivator bath and electroless copper bath. Most of the process can be done at room temperature. We'll use PTH process chemicals from Enthone-OMI as an example. Circuitprep 3023 is used to prepare the acid predip bath. It is a low acid solution to replace a bath of high concentration hydrochloride acid. An immersion for 1 - 2 minutes in Circuitprep 3023 is sufficient to attain balance in the activator bath. The preparation of this bath is simple, 100% concentration is needed. It should be noted that no water should be allowed from this bath onward until the PTH process is completed.

The next bath is the Circuitprep 3316 palladium catalystic process. Major ingredients are palladium chloride and hydrochloric acid. This is a catalyst for electroless deposition on insulators. This process should provide uniform void-free metal coverage in holes and good electroless copper to copper clad adhesion.

The next bath is the Circuitprep 4044 postactivator process. Working in conjunction with CP3316, CP4044 accelerates the initial deposition of copper onto an activated surface. Mechanical agitation is required to ensure the removal of air bubbles in the holes and a complete wetting of the PCB. The active ingredient is fluoboric acid. It remove the protective stannous from the CP3316 so that electroless copper can adhere to the activated surface easily.

Enplate CU-406 concentrates are used for electroless copper disposition. Heater is normally required in electroless copper bath. The solution itself is highly unstable and we made use of its thermal property to restrict the displacement of copper from the solution. Thus, depending on the formula, temperature can be used to control the process so that it won't precipitate all the copper when the solution is idling. In fact, a cooling coil can be installed in the bath to cool it down to around 12 ° C to save it for a longer period in time.