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In the large market of China, standard parts include bolts, screws, studs, nuts, machine screws, self tapping screws, washers, pins, rivets, retaining rings, pin keys, expansion bolts, rigging, industrial and mining construction, irregular screws, various equipment, steel, molds, and other standard parts in various industries. Mechanical components that are also widely used in various industries, their function is to connect various parts, just like in the case of airplanes, which are connected and fixed by various standard components to achieve permanent connections. These connections can also be disassembled before making related connections. This can prevent damage to certain components and enable timely repair.

Bolts belong to a type of fastener, and the surface of bolts includes stainless steel, zinc plating, nickel plating, etc. So, how can these types of bolts be distinguished?

Distinguish from appearance

Firstly, it is distinguished by color: stainless steel is the primary color of iron, galvanized screws are white, colored, or black, and nickel plated screws are silver.

1. Stainless steel screws are made of stainless steel material, and the color of stainless steel is mainly an alloy of iron and carbon, so the color is close to that of iron;

2. The surface of galvanized screws is galvanized with white zinc, colored zinc, black zinc, etc., so the colors of galvanized screws are generally white, colored, and black;

3. The color of nickel plated screws is related to nickel, usually presenting a very bright silver color.

Other differentiation methods

1. Distinguished by magnets: Stainless steel generally does not have magnetism, and what cannot be adsorbed by magnets is stainless steel screws. Galvanized and nickel plated screws can be adsorbed by magnets.

2. Distinguish with oxidants: Metal nickel has strong passivation ability, and during electroplating, an extremely thin passivation layer can be quickly generated on the surface. Therefore, the surface of nickel plated screws has a passivation film, while the galvanized surface is a layer of zinc. The stainless steel surface has nothing, and can be distinguished with strong oxidants.

3. Distinguished by strong acids and strong alkalis: Stainless steel contains chromium and nickel, which have strong corrosion resistance and are not corroded by strong acids and strong alkalis. The surface of nickel plated screws has a passivation film, which is slowly corroded by strong acids and strong alkalis. Galvanized screws are corroded the fastest.

Summary: The method to distinguish stainless steel screws, galvanized and nickel plated screws from their appearance is to look at the color of the screws. The color of stainless steel screws is close to the original color of iron, while galvanized screws are white, colored, and black, and nickel plated screws are very bright silver. In addition, magnets, oxidants, and strong acids and alkalis can also be used to distinguish stainless steel screws, galvanized and nickel plated screws