Multi-layer circuit board plating nickel gold plate reason analysis, tin can be studied from the following aspects to adjust 。
1, and false gold plating layer, and nickel layer washing time is too long or oxidation passivation, pay attention to pure water and strengthen the use of hot water washing time control.
2, electroless nickel plating or nickel cylinder problem: pollution heavy metal pollution agents, recommended low current electrolysis or active carbon filter element, PH value, dilute sulfuric acid or abnormal nickel carbonate, nickel coating thickness adjustment can be not enough, porosity is too high, check nickel plating current density, current on the table to check the current rod current and instrument display current time consistency, nickel, when necessary to do metallographic view Observe the thickness and surface condition of nickel layer; This can occur with low/high slot additives between nickel plating layers, but the additives may be lower. In addition, the nickel chloride content has little effect on the solderability of the nickel layer, with a focus on optimal value adjustment, high strength, and large and high porosity in the lower layers.
3, electroplating pretreatment: oil removal, acid recently low temperature, there may be a part of resistance welding PCB board proofing surface residue or film/can not deal with the network, can adjust the temperature, concentration in oil/also pay attention to other cavitation depth and plate surface uniform skin color.
4. Bad post-processing; After washing should be timely dry, well-ventilated place, preferably not in the plating workshop!
5. Other multilayer circuit boards are also worth noting that the quality requirements of all chemical treatment and clean water are higher than those of general electroplating. ! ! ! ! General municipal water/tap water, circulating water/well water lake is recommended not to use, because of the hardness of the water/contains other complex organic substances! Keyou Circuit is a professional production of high precision multilayer circuit board, module gold circuit board, vehicle circuit board, traffic recorder,COB power supply, computer motherboard, medical circuit board, module Bonding board, thermoelectric separation copper substrate, etc., quality assurance, delivery on time, to sales as one of the high-tech enterprises.
How to save cost and maintain quality of the circuit board
In recent years, with the increase of labor cost and raw material price again and again, many customers began to require product price reduction to save costs. circuit board manufacturers just located in the middle of the whole food chain, we do circuit board, the next to face plate suppliers and other auxiliary material suppliers of the price, to face the customer requirements of the price reduction, but also in the face of the growth of labor costs, we all racking their brains to think of how to save costs and to ensure quality.
Batch delivery of the circuit board is based on the basis of proofing, only after the sample qualified, the product can be mass-produced. If the size of the product is large, the one-time production can be satisfied. However, if the size of the product is small, the one-time material will produce inventory after delivery. If the customer samples are directly mass produced through OK, less material can be added during mass production. Can empty the inventory, but if the customer sample test is unqualified, need to revise, then the inventory can only be scrapped. In order to solve this problem, we can choose the same material, the same plate thickness and the same process of the product, and make it together, which has achieved the effect of reducing inventory and saving cost. When the appearance of customers' products is irregular, we can not according to the ordinary style of the plate, according to its different shapes, design inverted, concentric circles or two large boards with small boards in the middle of the way to improve the utilization rate of the board, save costs.
Shenzhen Circuit Board Factory: How to disassemble the integrated circuit on the circuit board
In circuit maintenance, it is often necessary to remove the IC from the printed circuit board. Because the IC pins are many and dense, it is difficult to remove, and sometimes it will damage the IC and circuit board. Here, Shenzhen Circuit board factory Xiaobian found several effective integrated circuit disassembly methods for your reference.
1. The use of tin absorber to remove the integrated block, this is a common professional method, the use of tools for ordinary suction, welding dual-purpose electric iron, power above 35W. When removing the integrated block, just place the heated dual-purpose electric soldering iron head on the pin of the integrated block to be removed. After the solder joint is melted and sucked into the fine tin, the integrated block can be removed after the solder of all the pins are sucked.
2. Medical hollow needle disassembly method to take medical 8 to 12 hollow needles several. When used, the inner diameter of the needle is just over the pin of the integrated block. When disassembling, melt the pin solder with the soldering iron, cover the pin with the needle in time, then remove the soldering iron and rotate the needle, and pull out the needle after the solder solidifies. This allows the pin to be completely separated from the printed board. After all the pins have been done this way, the block can be easily removed.
3. Electric iron brush with disassembly method This method is simple and easy, as long as there is a electric iron and a small brush. When disassembling the integrated block, heat the electric iron first. When the soldering tin on the pin is melted at the melting temperature, use a small brush to sweep away the melted solder. This separates the pin of the block from the printed board. The method can be carried out separately or separately. Finally, pry off the block with pointed tweezers or a small "one" flathead screwdriver.
4. This method is a saving method. As long as some solder is added to the pin of the integrated block to be dismantled, the solder joints of each column of pins are connected, so as to facilitate heat transfer and facilitate disassembly. When disassembling, each row of pins heated by electric iron should be pry with pointed tweezers or small "one" flat-head screwdriver. The two rows of pins should be heated alternately until removed. Normally, each column of pins can be removed after heating twice.
5. Multi-strand copper wire tin absorption disassembly method is to use multi-strand copper core plastic wire, remove plastic skin, the use of multi-strand copper core wire (can use short wire). Before use, put rosin semen on multiple strands of copper core wire. After the electric soldering iron is hot, put multiple strands of copper core wire on the integrated block to heat, so that the solder on the pin will be absorbed by the copper wire, and the part that absorbs the solder can be cut off. Repeat several times and all the solder on the pin can be sucked away. If possible, the woven bag in the shield line can also be used. As long as the solder is sucked up and gently pry with pointed tweezers or a small "one" screwdriver, the integrated block can be removed.