Mirror stainless steel surface polishing process analysis

Keywords.stainless steels;Polishing; Polishing Traditional Processes; Chemical Mechanical Polishing Methods

Stainless steel after nearly a hundred years of development process it, because it has a unique corrosion resistance, with good processing performance, and exquisite surface appearance, so stainless steel is used in many fields, especially in aerospace, atomic energy, military, light industry, building materials and solar energy use and other aspects of popularity and promotion. Nowadays, the building decoration market is changing rapidly, the grades of decoration are gradually improved, and more and more mirror stainless steel decorative surface has been used in the decoration. Polishing is a stainless steel used in the decoration industry is quite important in a link, the purpose is to obtain the final mirror (8K) stainless steel.

1 Evaluation of surface polishing quality of mirror stainless steel

8K surface, that is, mirror polished surface, its reflectivity is high, the reflection image is clear, measure the quality of mirror stainless steel is usually used to resolve the degree and surface defects rate, the evaluation is generally used to visually operate, there is a literature in the head of the following criteria: 1 level, is the surface is as bright as a mirror, can clearly see people's features as well as eyebrows; 2 level is the surface is bright, can see the human Level 2 is a glossy surface, can see people's features and eyebrows, but the eyebrow part is not very clear; Level 3 is a better surface gloss, can see people's features and outlines, the eyebrow part appears to be fuzzy; Level 4 is the surface is glossy, but can not see people's features; Level 5 is the surface is not glossy, presenting the departure of the white state.

2 Stainless steel polishing traditional process

The polishing techniques mainly used to obtain high quality mirror surface stainless steel are, electrolytic polishing, chemical polishing, mechanical polishing.

Electrolytic polishing

In the electrolytic polishing process, this is a stainless steel to be immersed in the electrolyte polishing method, in the process, stainless steel acts as the cathode, the use of direct current flow through the electrolyte specific kind of solution to the metal, and then in the stainless steel workpiece to be polished on the surface of the anode to form a thick mucous membrane with a high electrical resistivity, such thick mucous membrane in the stainless steel products surface of the microscopic bump in different locations The thickness of the thick and heavy mucous membrane film covered with the relevant thick and heavy mucous membrane film is not the same where the situation is caused by this, resulting in the anode surface current density of the micro-distribution is no longer uniform state, in the raised places where the current density is larger, dissolved more quickly, located in the concave places where the current density is smaller, dissolved more slowly, so it can be in the stainless steel Products on the exterior surface of the effective reduction of its roughness, significantly improve its degree of smoothness and brightness and lustre effect at the same time, but also to form a smooth passivation layer on its surface will not appear any defects.

In the case of an electrolytic polishing solution, it must contain a sufficient amount of oxidising agent and must not contain reactive ions that would damage the passivation film.

chemically polished

Chemical polishing and electrolytic polishing principle is similar to the stainless steel placed in a specific composition of the solution, the surface of the microscopic raised part of the dissolution rate than the microscopic concave part of the dissolution rate is faster, and then let the stainless steel surface becomes flat and smooth. Can understand, chemical polishing method and electrolytic polishing method of the principle is largely the same, just electrolytic polishing with the help of voltage electrolysis to accelerate the dissolution of the raised part of the forced action, and chemical polishing method completely by virtue of the self-corrosion of the solution to make the surface of stainless steel flat.

mechanically polished

Using a high-speed rotating polishing wheel adhering to a polishing paste, the unevenness of the surface of stainless steel is mechanically eliminated, resulting in a bright surface processing method, which is called mechanical polishing. Polishing wheels are differentiated in terms of particle size according to the type of fabric they are made of, and their structural forms are mainly of the sewing type, folding type, and so on. Among the materials required for polishing, there is a green polishing paste consisting of chromium oxide, which has a strong polishing ability, and a binder, and there is also a polishing wax consisting of abrasives, organic paste, and additives.

Mechanical polishing in two steps, first rough polishing, and then fine polishing, two stages step by step, with the help of different polishing paste and polishing wheels, in the mechanical rotating role, and ultimately be able to obtain a mirror surface stainless steel, its reflection image is clear, accompanied by stainless steel cold rolling process technology enhancement, the domestic able to stabilise the output of the surface of the stainless steel coarse.