Surface treatment plays a crucial role in maintaining the quality and performance of stainless steel plates. Stainless steel, known for its excellent corrosion resistance and durability, still requires proper surface treatment to enhance its properties and extend its service life.

Unlock the true potential of your stainless steel plates with effective surface treatment processes! If you’re in the market for high-quality, corrosion-resistant treated stainless steel, look no further than FOSHAN TOPSON STAINLESS STEEL CO., LTD. Surface treatment processes such as passivation, pickling, and degreasing oil play a crucial role in enhancing the performance and appearance of stainless steel plates.

This article overviews three common surface treatment processes for stainless steel plates: passivation, pickling, and degreasing oil. Each method serves a distinct purpose and offers unique benefits regarding corrosion resistance, surface cleanliness, and appearance.

Table of Contents

Surface Treatment Processes of Stainless Steel

The surface treatment of stainless steel plate is divided into many kinds: sandblasting, passivation, electroplating, pickling, painting, oil degreasing and rust removal, anodizing and so on. Although highly corrosion-resistant, stainless steel plates require surface treatment to enhance their performance and appearance. The basic and common methods employed are passivation, pickling, and degreasing oil.

Passivation is a chemical process that aims to remove any free iron or iron compounds from the surface of stainless steel. This helps create a passive chromium oxide layer, providing added protection against corrosion.

Pickling involves using an acid solution (typically nitric or hydrofluoric acid) to remove impurities like scale and welding oxides from the surface of stainless steel plates.

Degreasing oil removes grease or oil residue on stainless steel plates before further processing or application. It ensures proper adhesion during subsequent treatments like painting or coating.

Each surface treatment process serves different purposes but ultimately enhances the quality and longevity of stainless steel plates. Stay tuned as we delve deeper into each method in our upcoming sections!


Passivation is a surface treatment process commonly used for stainless steel plates. It involves the removal of iron contaminants from the surface, which can help improve corrosion resistance. This process typically uses an acid solution or other chemical agents to dissolve any iron particles on the surface.

During passivation, a protective oxide layer is formed on the surface of the stainless steel, which helps prevent further oxidation and corrosion. This oxide layer is a barrier against environmental factors such as moisture and chemicals.

One of the key benefits of passivation is its ability to enhance the aesthetic appearance of stainless steel plates. Passivation can give stainless steel a clean and uniform look by removing any impurities or discolouration on the surface.

In addition to improving corrosion resistance and enhancing appearance, passivation also helps to promote better adhesion for subsequent coatings or treatments that may be applied to the stainless steel plates.

Passivation is important in ensuring optimal performance and longevity of stainless steel plates by protecting them from corrosive elements. It is important to note that the surface of the conditions using the passivation process cannot contain iron.



Pickling is one of the surface treatment processes commonly used for stainless steel plates. Its purpose is to remove the oxidation of the surface of stainless steel after high-temperature welding, heat treatment or hot working, such as oxides, scale, and stains. This process helps improve the stainless steel’s appearance and corrosion resistance.

During pickling, a strong acid solution is applied to the surface of the stainless steel plate. The acid reacts with any unwanted substances on the surface, dissolving them and leaving a clean and smooth finish behind. Pickling also helps to restore the passive layer on stainless steel that may have been damaged during fabrication or other processes.

One advantage of pickling is that it can be performed before and after fabrication. Pre-fabrication pickling removes mill scale and other impurities from raw materials, ensuring a clean starting point for manufacturing. Post-fabrication pickling removes weld scale and heat tint from welded areas.

It’s important to note that proper safety precautions should be taken when performing pickling due to its corrosive nature. Protective equipment such as gloves, goggles, and aprons should always be worn. The pickling process can be applied to all 200, 300, and 400 series stainless steel surface treatments.

Pickling is an effective way to enhance the quality and durability of stainless steel plates by removing impurities and restoring their corrosion resistance properties. However, it should be noted that if the acid on the surface of the stainless steel plate is not cleaned after pickling, the surface of the stainless steel plate will soon be corroded and rusted.


Degreasing Oil

Degreasing oil is a surface treatment process to remove oil, grease, and other contaminants from stainless steel plates. It involves the application of a specialized oil-based solution that effectively dissolves and lifts away surface oils and greases, leaving the stainless steel clean and free from residue. The primary purpose of degreasing oil is to ensure a pristine surface ready for subsequent processes or applications.

Using a targeted degreasing oil, these unwanted residues can be effectively removed without causing any damage to the underlying metal. The oil breaks down the molecular bonds between grease molecules and the stainless steel surface, allowing them to be easily wiped away.

In addition to removing visible greasy residues, degreasing oil helps prepare the stainless steel surface for further processing or treatments such as passivation or pickling. It ensures that all traces of grease are eliminated before moving on to subsequent steps in the surface treatment process.

Steps Involved in the Degreasing Oil Process:

Surface Cleaning and Degreasing. Before applying degreasing oil, the stainless steel plates are thoroughly cleaned to remove any loose dirt or debris. This can be achieved through mechanical cleaning methods such as wiping, brushing, or rinsing with water.

Application of Degreasing Oil. The degreasing oil is applied to the surface of the stainless steel plates either by immersing them in a bath of the oil solution or by spraying it directly onto the surface. The oil penetrates and dissolves the oil and grease contaminants, loosening their bond with the stainless steel.

Removal of Excess Oil and Drying. After the degreasing oil has had sufficient contact time with the surface, any excess oil and dissolved contaminants are removed. This can be done by rinsing the plates with water, wiping them with clean cloths, or using both methods. The plates are then thoroughly dried to prevent the formation of water spots or residual moisture.

Degreasing oil effectively eliminates oil, grease, and other organic contaminants from the surface of stainless steel plates. On the other hand, removing oil and grease and degreasing oil helps prevent staining and discolouration when these substances react with the stainless steel surface. This is particularly important for applications where aesthetics and surface appearance are critical.


Comparison of Passivation, Pickling, and Degreasing Oil

Passivation, pickling, and degreasing oil are three common surface treatment processes for stainless steel plates, each serving distinct purposes.

Passivation enhances the corrosion resistance of stainless steel by removing surface impurities and forming a protective oxide layer. Pickling removes scale, rust, and oxide layers, restoring the surface finish and appearance. Degreasing oil effectively removes oil, grease, and contaminants, preventing staining and discoloration.

In terms of application, passivation is often used in industries where cleanliness and hygiene are critical, such as pharmaceutical or food processing. Pickling is commonly employed in applications where a smooth finish is desired, such as architectural projects or automotive components.

In conclusion, passivation is ideal when high corrosion resistance is needed while maintaining aesthetic appeal; pickling gives a smoother finish, whereas degreasing oil is critical for removing grease and oils to ensure proper surface preparation. Each treatment has its place in achieving optimal results for different applications involving stainless steel plates.

Factors Influence the Choice of Surface Treatment Process

Factors influencing the choice of surface treatment process for stainless steel plates are crucial in ensuring optimal results. Several key factors should be considered when selecting the most suitable method.

One important factor is the desired outcome and purpose of the treatment. Passivation, pickling, and degreasing oil all have different effects on the surface of stainless steel.

The type of stainless steel being treated also plays a role in determining the appropriate method. Different grades of stainless steel may require specific treatments to achieve desired results without damaging the material’s integrity.

Environmental considerations are another factor to consider. Some processes may involve hazardous chemicals or generate harmful byproducts, so selecting a treatment that aligns with environmental regulations and safety protocols is crucial.

Cost-effectiveness is an essential consideration as well. The chosen treatment must provide satisfactory results while fitting within budget constraints.

Time constraints can influence decision-making. Some treatments require longer processing times than others and may not be feasible if there are strict deadlines or production schedules to meet.

Selecting the appropriate treatment process depends on the specific application requirements. For applications demanding high corrosion resistance, passivation is typically preferred. Food processing, pharmaceuticals, and medical equipment industries often require passivated stainless steel. Pickling is commonly used in architectural applications or when corrosion resistance and surface appearance are important.

Degreasing oil is suitable when surface cleanliness and prevention of staining are the primary concerns, such as in kitchen equipment or decorative items.

PVD stainless steel


Surface treatment processes play a crucial role in enhancing the performance and aesthetics of stainless steel plates. Passivation, pickling, and degreasing oil are three commonly used methods that serve distinct purposes.

Several factors should be considered when selecting the most suitable surface treatment process for your stainless steel plates. These include the desired level of corrosion resistance required for your specific application, environmental concerns related to chemical usage or waste disposal practices, and cost considerations.

You can decide which method best suits your needs by understanding these options for treating stainless steel surfaces. Remember that each process serves a different purpose but ultimately contributes to maintaining durability and aesthetics while prolonging the lifespan of your stainless steel plates.

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