Sometimes, we found that during the transportation proc […]
Sometimes, we found that during the transportation process, it was found that the zinc coating of the screw often appeared white, black, black and other phenomena. In fact, this is a phenomenon of corrosion. In this case, we have to deal with it in a timely manner. Avoid more serious situations. Perhaps many people do not know that these situations will occur with screws, so we must understand clearly, then let's take a look at what happens when the screws are aging?
In order to prevent non-standard screw anti-corrosion treatment is already degreasing, and in the Nasdaq anti-rust agent water tank anti-rust screw nut swim freely, or use a zinc and chromium compound to form a protective film on the metal surface, forming a spray method, and Dry, cool, and then repeat the process once, and the resulting thickness of about 5 to 8 μ, silver gray, based on the information provided by the manufacturer of the display is said to have good rust and corrosion resistance
Phosphate treatment is a chemical treatment of phosphate containing metal to metal surface to form a phosphate protective film phosphating treatment solution, which is insoluble in water, and has excellent adhesion of phosphate coating, as its main purpose bottom layer and coating Metal layer that cold adsorbs lubricant. Since the phosphate coating is composed of a series of zinc, manganese, hydrogen phosphate and iron phosphate crystals of different sizes, the membrane is porous, has a large specific surface area, and has good absorption, adsorbed coatings or a large amount of lubricant Often, so it is often used as a primer, or cold stamping to reduce friction and steel, cold-drawn steel wire lubrication layer.
The oxidized steel parts will be immersed in an alkaline treatment solution containing an oxidizer, such as potassium hydroxide or sodium hydroxide solution of nitric acid, and maintain its boiling point at about 140 ℃, or nitric acid and sodium hydrogen nitrate impregnated molten steel It is pleasing to remove its surface layer, and the eyes with black iron oxide film in the composition with a mixture of ferrous oxide and iron oxide can be obtained and then quenched in water, which is a method to improve the corrosion of ferrous metals.