What is stainless steel surface mirror polishing? To what extent can it be considered a mirror?

In layman's terms, polishing stainless steel can make the surface of stainless steel bright and clear. Mirror stainless steel surfaces can be classified into 8k, 10k, and 12k according to their grades. The higher the grade, the better the brightness and surface effect! In other words, mirror polishing of stainless steel surface is a type of surface treatment that reflects the metallic nature (similar to mirror reflection) by removing surface roughness and oxide scale. Generally, the surface roughness value Ra ≤ 0.05 μ m and surface smoothness greater than 10 are required to be called "mirror".

Stainless steel polishing can be divided into strip and plate, as well as different materials and thicknesses. Different materials and thicknesses are divided into different polishing methods! The commonly used polishing methods at present are mechanical polishing, chemical polishing, and electrolytic polishing!

At present, the commonly used mirror polishing equipment mainly rotates stainless steel plates or other types of metal plates counterclockwise through adjustable pressure grinding discs, and the correction wheel drives the workpiece to rotate. The workpiece is pressurized by gravity, and a matching grinding emulsion (mainly composed of metal oxides, inorganic strong acids, organic lubricants, and weak alkaline cleaning agents) is added to achieve the purpose of grinding and polishing by relative friction between the workpiece and the grinding disc. Mirror polishing machine can be divided into three steps: grinding, polishing, and repairing; The matched abrasives, grinding materials, and grinding fluids also vary depending on their different production stages.

Stainless steel plates of various materials and thicknesses can be processed into different degrees of mirror effect; Due to the macroscopic roughness of the base material (whose surface roughness Ra value is generally da), it is necessary to first grind its surface roughness to a certain value (Ra ≤ 0.8 μ m) through grinding, and then grind it to a "mirror surface" through polishing and grinding.

There are many surface states of stainless steel, and the surfaces commonly used as mirror polishing master materials include 2B, 2BB, 2D, BA, No.1, etc. The materials suitable for mirror polishing are mainly SUS304304J1, The final mirror effect of austenitic and ferritic stainless steels such as 316L and 201202430441 is also determined by the material and surface of their base materials; Generally speaking, the grinding effect of 300 series stainless steel is slightly better than other series materials, with BA having the best surface grinding effect, followed by 2B, and No.1 having the worst.

In addition, the polishing emulsion, polishing machine and polishing emulsion circulation system come into contact, and there are various acidic and alkaline substances that corrode, requiring both the polishing emulsion and polishing machine to have good corrosion resistance. In addition, due to the high-speed rotation of the polishing machine and the friction of the metal plate, a large amount of heat is generated (especially for austenitic stainless steel, which has poor thermal conductivity); Due to the fact that grinding work generates a large amount of heat in the same area, it can cause changes in the surface stress of the metal, thereby affecting the slight changes in the physical state of the metal and ultimately leading to the flatness of the metal. Therefore, it is required that polishing equipment and polishing environment have good heat dissipation conditions.

Generally, mirror stainless steel strips can be polished to a thickness of 0.05-1.5mm, while plates can be ground and polished to a thickness of 1.0-3.0mm. The materials can be divided into 201, 304, 301, 316, 430, 444, etc!

The polished stainless steel is called mirror stainless steel or 8K stainless steel, which has a wider range of applications and can be used in industries such as decoration, home furnishings, electronics, mobile phones, decoration, automobiles, elevators, etc!