The surface finish of stainless steel affects not only its aesthetic appearance but also its performance and other aspects. It's crucial to make the right choice depending on the intended use. Surface finish determines factors like corrosion resistance, electrical properties, and weldability and may require specific finishes for certain applications like superconductor components or flexible metal hoses. Additionally, terminology may vary among suppliers, so it's essential to understand these differences. 

Surface finish refers to the visual appearance of the metal and is achieved through various processing methods. These finishes range from matte to highly polished, influenced by factors such as production methods, material thickness, roll surface condition, cleanliness, and mechanical abrasion.

Most melt mills can produce a variety of finishes, but precision re-rolling may be necessary to meet unique customer requirements for surface roughness.

Mill finishes are the standard supply condition for all stainless steel sheet products, whether hot or cold-rolled. They serve as the starting point for various finishing processes and are often acid-cleaned to maximize corrosion resistance by removing scale build-up from hot rolling and annealing (with the exception of bright annealed finishes). 

NO.1 FINISH

It is finished through annealing and pickling after the hot rolling and heat treatment processes. This results in a dull finish and is primarily used when a smooth decorative finish is not essential. It is commonly employed in industrial applications where corrosion resistance is a top priority, such as the fabrication of tanks and chemical industrial equipment, and in high-temperature applications.

NO.2D FINISH

A 2D finish is achieved through cold rolling, followed by heat treatment and descaling. It results in a non-reflective and dull surface. This finish is ideal for products that require corrosion resistance but don't need a reflective surface. It is commonly used in applications where deep drawing capability is essential. You can find it in auto exhaust components, hardware, and chemical equipment. 

NO.2B FINISH

A 2B finish is achieved through cold rolling, followed by annealing and acid pickling, and a light temper pass using polished rolls. It results in a smooth, somewhat reflective, and bright surface. This finish is generally suitable for most applications and is commonly used in cookware, small tanks, pharmaceutical equipment, and various other purposes.

NO.3 FINISH

A No. 3 finish, also known as grinding, roughing, or rough grinding, is achieved using a 100-120 grit option applied in a one-directional course. This finish requires specialized coils or rolls for mechanical or gradual and refined polishing techniques. It is commonly used in various applications, including kitchen equipment for food and beverage production, architectural interior and exterior surfaces, and the appearance of various electronic products. 

NO.4 FINISH

A No. 4 finish is characterized by a bright appearance with short, uniform parallel polishing lines achieved through a 150-180 grit option. It has a finer abrasive state compared to No. 3 and presents an attractive silver-white surface. This finish is widely used in various applications, including kitchen and restaurant equipment, food processing, dairy equipment, hospital surfaces, highway tank trailers, control panels, and water fountains. 

NO.6 FINISH

A No. 6 finish is achieved by Tampico brushing a No. 4 finish. It has a dull, silver-white appearance and is less reflective than a No. 4 finish. This finish was commonly found on stainless steel architectural components up until the 1980s but is much less used today. It's also known as Satin Finish and has a finer abrasive state compared to No. 4. It is used when an elegant surface with removed shine is desired, typically achieved through methods like Tampico Brush or Scotch Brite. 

NO.7 FINISH

A No. 7 finish is achieved by buffing a finely ground surface. This finish has a high luster with visible grit lines on the material, creating a reflective, almost mirror-like appearance. It is commonly used in applications such as column covers, ornament trim, and wall panels. This finish is created by buffing the surface with 400-600Mesh abrasive material, and some traces of the abrasion may still be visible. It is primarily used in the dairy industry for tank equipment, architectural decoration, and industrial purposes. 

NO.8 FINISH

A No. 8 finish is achieved by polishing with successively higher grit abrasives and then buffing for a mirror finish. According to ASTM standards, it is the most reflective of all finishes. Because of its high reflectivity, No. 8 finishes find notable everyday applications, including press plates, signs, and wall panels.

It is produced using abrasive materials of 800Mesh or higher, and buffing is done to create a mirror-like finish. While the standard is to have minimal abrasive traces visible, the production cost and method may vary depending on the level of polishing, so it is typically produced based on samples.

HL(Hearline) FINISH

HL products are achieved by using abrasive materials of appropriate particle size to create continuous abrasion marks on a No. 4 finish. Due to the continuity of these abrasion marks, it is widely used in South Korea as architectural cladding material for both interior and exterior applications. 

Light HL FINISH

​A Light Hairline finish is a product achieved by creating continuous abrasion marks on a No. 6 Finish substrate, resulting in a smoother and more elegant appearance compared to the traditional HL finish. Its applications are similar to HL and are primarily used for coloring and etching. It can be used for various purposes, including the interior of microwave ovens, and it is a recently developed product with expanding applications.

BA(Bright Annealed) FINISH

BA products are achieved through cold rolling followed by bright annealing and a slight cold-rolled skin pass, resulting in a highly reflective surface. It is commonly used for appliances and appliances requiring reflectivity, such as household appliances and panels.

BP(Bright Pickling) FINISH

BP products are obtained by performing a low-temperature pickling process after cold rolling, resulting in a surface known as "Bright Pickling." It also undergoes a slight cold-rolled skin pass. It is used as an alternative to BA (Bright Annealed) finishes. 

DULL

A dull surface is a matte finish produced by grinding with a fine rugged roll. Widely used for the exterior and interior of trains and buildings that require reduced light reflection. 

EMBOSSED

Produced by rolling the pattern into the product. Embossed metals is especially popular in high traffic areas. 

COLORING

This product utilizes the interference phenomenon of light through electrochemistry on the surfaces of No. 2, BA, and HL finishes to introduce color. After coloring, it undergoes a passivation treatment, resulting in superior corrosion resistance compared to the No. 2B state, and the color quality is excellent. It is available in various standard colors such as blue, green, red, gold, and black, and multiple colors can be achieved through repeated processes. Its applications include interior architectural materials, the exteriors of household appliances, watches, decorations, and it is a product that has seen increasing diversification in recent developments. 

ETCHING

This product is selectively etched on No. 2B, BA, and HL finishes to create decorative effects. It can be produced using two methods: photochemical and silk screen techniques. Its main applications include interior and exterior architectural materials, elevators, escalators, panels, nameplates, and various other uses. 

ETCHING COLORING

This product combines coloring and etching to create a harmonious blend of beautiful patterns and colors. It is a recently developed product, and its purpose is similar to that of etching and coloring products.

The information provided on this webpage is intended solely for informational purposes. Steeltopia does not make any explicit or implied representations or warranties regarding the accuracy, comprehensiveness, or validity of this information.