Nanocrystalline coating copper process introduction

Nanocrystalline copper coating of epoxy powder coating process and requirements Because of the nanocrystalline core is 20 ~ 40 um thin tape winding after heat treatment, the sensitive to stress and in the process of painting and use easily affected by stress caused by unstable performance. Coating is required in the process of coating does not produce larger stress, the coating after curing needs to have larger hardness, space stability, good adhesion, good insulation properties, even in the inductance of the subsequent processing may encounter some organic solvents, need the coating can have good solvent resistance. Because of the nanocrystalline core is basically a ring structure, cannot like other artifacts of powder coating spray can be hung up. Again because the core after winding itself is relatively soft, to thin wall or larger magnetic core can't like other core coating to wear, otherwise easy to deformation. And no lead Angle of the magnetic core, how can coated edges, it puts forward higher requirements on spraying process. According to the above characteristics of the magnetic core through the development of powder coating and coating process to improve the surface coating way anyway, not only guarantee the performance of the nanocrystalline core and greatly improved the efficiency of the magnetic core of nanocrystalline coating. Here is a simple introduction of the process.

Powder coating is with powder spraying equipment (electrostatic spray molding machine) to the application of the powder coating the surface of the workpiece, under the effect of static electricity, the powder will be adsorbed on the surface, homogeneous form powder coating; Flat curing powder coating after high temperature baking flow, into a different effect (different types of powder coating effect) of the final coating; Powder coating spraying effect on the mechanical strength, adhesion, corrosion resistance, ageing resistance, etc, is superior to the painting process. The main component of powder coating system A set of electrostatic powder coating system for powder is mainly composed of a set of devices, a set or several sets of electrostatic spray gun and control device, electrostatic generator (usually configuration in electrostatic spray gun) and a set of powder recovery unit.

(1) device for powder In device for powder, the powder in a fluidized state, which is accomplished through the role of compressed air, after powder by siphonage airflow with high speed flow, forming powder mixed gas, through venturi powder pump, powder duct, eventually reach the spray gun. Conveying to the spray gun powder can be regulated, specifically is can adjust the powder and the parameters of the air, respectively, to change the quantity of powder and powder spray pattern, which can realize different film thickness, meet the needs of different products. For powder device has sufficient capacity, even though the gun powder duct 50 feet long and can also provide enough pressure and flow rate.

(2) on the high voltage static electricity generated by the electrostatic generator, low current that located at the front of the spray gun needle electrode discharge in air, when the powder by the spear head nozzle, powder particles is taken charge, by electrostatic adsorption and air transportation the dual function in order to have the ground surface of workpiece. Spray gun can produce enough voltage to ensure maximum coating effect, maximum voltage is 100 kv, when spraying angles or deep cavity spray gun can effectively overcome the Faraday cage effect, ensure every asked to spray the surface of the workpiece can achieve good coverage and uniform film thickness.

(3) the structure of the spray gun gun design must satisfy the requirement of the powder charging, functional design must meet all kinds of spraying operation and various shapes of workpieces coating requirements. Powder coating is a new coating technology on the surface of the process, in powder form film was formed by coating and coating process. In a variety of occasions can replace the traditional paint process. At present, has been widely used at home and abroad. Compared with the paint process, powder coating has the advantage of

1) high efficiency: because it is a one-time film, can improve the productivity of 30-40%

2) energy saving, reducing energy consumption of about 30%

3) less pollution, no organic solvent volatilization (not including paint coating of the harmful gas such as toluene, xylene).

4) high utilization rate of coating: can reach more than 85%, and the powder can be repeatedly used after recycling.

5) coating performance is good: one-time film thickness can be up to 50-80 microns, the adhesion force, tensile resistance, wear resistance, hardness, corrosion resistance and so on comprehensive indicators are better than paint process.

6) high yield: in before curing, can be secondary spray.

(4) curing: after heated to proper temperature, keep enough time, epoxy powder curing can become a stable layer of film, the film has strong mechanical strength can be fixed and protect the core.

2. Process introduced pendulum core: blowing off nanocrystalline core surface adhesion of foam particles, and other impurities. To check whether there is crack, nanocrystalline core inside and outside welding if cracking to spot welding flat before coating. The nanocrystalline core evenly placed on the tray. Coating: according to the product requirement of coating thickness, appearance, adjust the parameters of the spray gun: the quantity of powder fluidization barrels, static voltage and air pressure. First take 5 ~ 10 core coating, examine the coating effect, if the parameter suitable to mass production. Curing: according to the requirement of the epoxy powder, set up the curing temperature, curing furnace and keep the temperature. The powder curing temperature is between 180 ℃ ~ 200 ℃. Put good coating nanocrystalline core in curing furnace keep 10 ~ 20 min (this parameter depends on powder requirement). Flip: after powder curing completely, taken from the furnace cooling, and then using turnover to reverse it. Examines: the coating after the first visual check nanocrystalline core coating thickness and uniformity, exterior flatness, inside and outside edge covering effect, after the appearance of qualified through test instrument test performance. Packing: according to the size of the nanocrystalline core and coating thickness to choose the right means of packaging, to ensure that the nanocrystalline core transportation would not break the way and affect performance. Capacity analysis: coating curing flip coating curing core quality packaging in place Is punctuated coating methods used by the coating way, the entire part time is mainly in curing coating process, coating required time is shorter, so the capacity is mainly limited in curing. Is 3 per shift production personnel, put nanocrystalline core and 1 turn, 1 coating, quality packing in 1 person. USES the oven curing, 18 can put inside an oven tray, two oven with production. Each the size of the tray is 500 mmx300mm, can be placed within the outer diameter of 20 mm nanocrystalline core 150. Coating capacity is 2700 a single production cycle, each cycle of the production time is 2 h, work for 8 hours, three shifts, under the condition of the normal production of maximum capacity can reach 32400 every day, work 26 days a month, the quantity can reach 840000. If adopt the way of curing tunnel furnace, four people eight hours a day can be coated core for more than 100000.

Third, the quality control

Quality control mainly by nanocrystalline core stability, epoxy powder, equipment, process fixed, employees, and the operation of skilled and professional degree, and the quality detection to control the shipment.

1 incoming material control, customer product appearance: visual check first iron core inside and outside welding is complete, if there is a core welding problems such as open, whether there is a transit lead to nanocrystalline core scattering problems. If there is a need to welding and nanocrystalline core test again. Performance: each batch of nanocrystalline core material extracted easily affect the nanocrystalline core in the process of transport properties of nanocrystalline core test.

2, epoxy powder of the preservation and preservation conditions of use: epoxy powder under the condition of normal temperature preservation of no more than 6 months, can appear otherwise the powder coating gel, lead to coating performance and appearance will have greater impact. Recommended storage condition is sealed in the refrigerator to keep in 6 ℃, the conditions can be very good avoid powder due to heat damage. Test: model to ensure that every time before spraying spraying powder not bad. Powder recycling: to ensure recovery system without any pollution, so that we can guarantee the recycling epoxy powder from pollution. Recycled powder according to the new powder: recycle powder = 3:1 ratio of use, must before each use recycle powder powder sieving.

3, equipment stability control lance: determined before coating spray gun static voltage, fluidized bed, atomization effect is normal. Spray: regular inspection spray filter, convulsions system is normal, powder bucket whether there is leakage, etc. Oven, regularly check the oven temperature is stable, heating and temperature uniformity is in line with the requirements.

4, fixed process Each type of product is different, every new product samples needed to be done and sent to the customer to determine, once determined after the process does not change, and in the form of table specification to each department, unless customer proposed improvements should be implemented strictly.

5, the operation staff training Each post staff are required to pass through rigorous training to mount guard, especially spraying station, need to receive professional training after the inspection qualified to mount guard. Operators need to be able to understand whether metamorphism, powder spray gun static voltage, atomization effect is in line with the requirements of the temperature of the furnace temperature is stable and whether meet the requirement of sieve plate whether meet the requirements of the coating.

6, the goods inspection and packaging First every single nanocrystalline core in the process of production need to detect the appearance, whether there are show the phenomenon, whether there is a dent; If there is a problem need to immediately stop production to find the problem, after waiting for problem solving, to production. After coating of nanocrystalline core part of each batch is need sampling test inductance, such as performance, such as unstable performance problems need to stop production immediately and timely communication with the customers. Based on the differences of nanocrystalline core coating film thickness, choose the appropriate packaging to ensure the transport process of nanocrystalline core will not be damage.