ã€China Aluminum Network】 I. Features:
1.DW-ALV is a quaternary cyanide-free zinc sinker, which can displace a layer of composite film containing zinc, nickel, copper, and iron on the surface of aluminum alloy. This replacement film has uniform crystal structure and has excellent adhesion.
2. Once the zinc is sinking (the effect of secondary zinc is better), Alkali copper, copper coke, and chemical nickel can be plated directly, saving manpower and time, and improving efficiency;
3. Can be used in rack plating and barrel plating.
4. It is more convenient to add and maintain a single open cylinder.
Second, the composition of the bath and operating conditions:
Third, build bath:
1. Add one-third of deionized water to the clean PVC tank.
2. Slowly add the zincizing agent metered with the bath solution under constant stirring, add sodium cyanide, stir to dissolve, and uniformly cool.
3. Make up for deionized water. Stir well. Adjust the temperature to the working range.
Fourth, process flow:
Hot dip oil removal - Cleaning - Immersion (depending on the aluminum alloy material) - Cleaning - Detergent film - Cleaning - DW-ATL Chemical zinc leaching - Cleaning - Electroless plating or electroplating 5. Plating solution maintenance:
1.DW-ALV aluminum zinc precipitant is strongly alkaline concentrated liquid. When using it, it should be handled with care. It should be added slowly under stirring to avoid local overheating and uneven concentration, resulting in rough work surface.
2. The working temperature is less than 30 °C, the temperature is too high, so that the zinc sink crystal rough, reducing the binding force of the substrate and the coating.
3. Production supplement principle: To add a small number of times, each processing 20d?/L workpieces need to add 1.2% of the cylinder opening.
4. The concentration of aluminum zinc sinking agent is too high, the formation of zinc replacement layer is loose and porous, it will also affect the binding force of the coating.
5. The time for the zinc sinks to go out of the tank and transfer to the water should not exceed 15 seconds.
Six, process technology description:
1. DW-ALV chemical immersion zinc is a uniform dark gray film. If it is found that the film layer is uneven, it should be checked whether the degreasing or etching process is operating well.
2. In the procedure of using secondary zinc dipping, the time of the second zinc leaching is shorter than that of the previous immersing zinc, about 10 seconds. After the previous zinc immersion, the zinc is decomposed with 50% nitric acid.
3. Difficult to clean the workpiece, after the DW-ALV chemical leaching process is cleaned, acid leaching with 0.5% sulfuric acid, and then cleaned, this can effectively prevent the immersion zinc solution from contaminating subsequent electroplating or electroless plating solutions.
4. The following factors will affect the effectiveness of DW-ALV chemical zinc immersion solution.
1. Solution concentration 2. Solution pH 3. Operating temperature 4. Zinc dipping time 5. Amount per treatment (in area)
6. The solution has been used time 7. Aluminum alloy composition 8. Workpiece surface conditions 9. Pre-treatment process VII, packaging; 25Kg / barrel statement: This manual all about the company's products recommendations and parameters, is based on the company's trust experiment and The data is standard. Due to the heterogeneity of the industry's equipment and actual operations, the company does not guarantee and is not responsible for any possible adverse consequences. All information in this manual is not used as evidence of copyright infringement.