Other factors affecting the corrosion resistance of double-layer nickel-iron alloy
In order to improve the rust resistance of the double-layer ferronickel-chromium composite coating, the process should be strictly controlled and the process management should be strengthened [5]. (1) Control of polishing before plating After polishing, the roughness is 3.2μm (▽6) on the surface of the double-layered nickel-iron alloy/chromium. The salt spray test shows no less than 1mm2 rust point, and the roughness is on the surface of 0.8μm (▽8) in the same process. Under the condition, no rust spots appear after plating, and it is seen that the roughness required for polishing is 0.8 μm or more. (2) Selection of additives Whether it is a single brightener or a commercial combination additive should be selected by a fixed-point professional factory, each batch of additives should be tested with a Hull tank, compared with the sample, check whether the rust resistance of the sample meets the requirements before it can be put into use. (3) Control of nickel-iron ratio in plating solution Corrosion tests were carried out after different nickel-iron ratios were plated under normal process conditions. The results are shown in Table 1 [5]. It can be seen from Table 1 that the test results of the test piece No. 1 are the best, that is, the iron content of the high-iron in the coating is 27.2%, and the low-iron content is 14.4%, and the corresponding high-iron plating solution is controlled by nickel and total iron. .3g/L and 4.76g/L are the best. (4) Coating thickness Coating thickness: The thickness of the high iron layer should be greater than 18μm, and the thickness of the low iron layer should be greater than 6μm. (5) Control of metal impurities in plating solution Nickel-iron coatings contain other metal impurities that directly affect their rust resistance. Concerned about surprises Label: Nickel-iron Coating Alloy Corrosion test Corrosion resistance Previous: Talking about the polishing characteristics of marble plates and their use and injections Next: The secret of corrosion resistance and non-aging of steel radiators Lvl Plywood,Bintangor Plywood,Furniture Plywood Linyi Chanta Plywood Co., Ltd. , http://www.lyplywood.com
