Surface processing method for high-strength blackened bolts

Surface processing method for high-strength blackened bolts

As the name suggests, high-strength blackened bolts have undergone blackening treatment on their surface, and their strength is relatively high, reaching 8.8 grade. They have a wide range of applications, especially in industries such as machinery, bridges, power facilities, and petrochemicals.

The principle of processing high-strength blackened bolts is mainly to create an oxide film on the surface of the bolts, which can isolate air, avoid rust and corrosion of the bolts, and improve the wear resistance of the product.

For situations where the appearance requirements are not very high, surface blackening treatment is generally performed, or some are called blueing treatment. Although the surface of the product has changed, the internal structure of the product will not change.

So how do high-strength blackened bolts undergo blackening treatment? In fact, the process of blackening is to acid wash, degrease, and heat the product, which will generate a layer of black or blue oxide film on the surface of the bolt. It should be noted that the heating temperature should not be too high to avoid deformation of the bolt.