Stainless Pretreatment Why and How

Table of Contents

The necessary for stainless pretreatment :

Pretreatment is vital for stainless steel parts before surface processing (including pickling, chemical polishing, electrochemical polishing, electroplating, passivation, blackening, coloring, chemical processing, etc.).

When forming stainless steel parts, the surface may be stuck with oil, burrs, rough surface, and oxides. Therefore, before surface treatment, oil, rough surface, and oxides must be removed before post-treatment to achieve satisfactory results.

Types of unnecessary things that are removed:

The dirt to be removed during the pretreatment of stainless steel surfaces can be divided into organic and inorganic substances.

  1. Organic contaminants, including mineral oils (such as diesel, engine oil, petrolatum, kerosene, etc.) and animal and vegetable oils (such as soybean oil, camellia oil, rapeseed oil, lard, tallow, etc.), mainly from When machining stainless steel parts, lubricants, cutting oils, quenching oils, polishing and polishing pastes, and fingerprints.
  2. Inorganic dirt. Including dirt, dust particles, oxides formed during heat treatment, and other impurities.

Steps :

  1. Smooth the surface, eliminate the roughness of the stainless steel surface, and achieve a perfect finish after mechanical polishing and buffing.

a specific surface texture,

  1. Degrease, and remove oil stains on the surface.
  2. Pickling to remove oxides from the surface.
  3. Weak corrosion activates the surface to be treated, removes the surface passivation film, and exposes the crystalline metal structure.

Pretreatment methods:

  1. Mechanical method: Use a grinder, polisher, or other machines to remove the rough condition of the surface for polishing and buffing.
  2. Applying the alkaline solution to remove oil, acid solution to pickle, and organic solvent to dissolve grease and decontaminates.
  3. Electrochemical processes, degreasing, and etching.
  4. Roller burnishing, spin burnishing, spin wheel polishing, and rotary polishing are suitable for small parts for leveling and descaling.
  5. Sandblasting is suitable for large area treatment, decontamination, and removal of deposits.

Finally, a suitable pretreatment method should be selected according to the different surface textures and quality requirements of stainless steel post-treatment.Read more hidden textYour long text