Stainless steel: different surface finishes

Mill finish – 2B | dull polished 240 grit | bright annealed | ultra bright

When you think of stainless steel, you may picture a dull polished finish. This is the kind of finish that you often see in commercial kitchens or on street furniture. Stainless steel is a versatile product available in a variety of different surface conditions. materials4me stock most popular surface finishes available. These vary from a mirror like reflective finish to a dull grey 2B finish.

The terminology used for stainless steel surface finishes can be confusing. They are often referred to by their trade descriptions, like 2B, BA, 240 grit, 240 silicon, descaled etc. This is our short guide on the most popular finishes available.

Mill finish – 2B

2B is the ‘raw’ surface of stainless steel. It is a dull grey, slightly reflective finish. This is what stainless steel looks like before it gets polished. Additionally, it may have inkjet batch numbers on the surface. Material with a 2B finish is a cold rolled product that is usually available in thicknesses from 0.5mm thick to 6mm thick. You would use 2B material where the surface finish isn’t visible or where you intend to polish the surface after fabrication.

Dull polished 240 grit

This is the classic dull polish finish. It is an appealing as well as practical surface finish for products such as door furniture and splashbacks. Dull polish has a grain that runs along the length of the original production coil. When the coil is cut into smaller blanks the grain may run along the width. Just like the descriptions on sandpaper in the DIY store 240 grit refers to the coarseness of the abrasive belt that was used to polish the sheet. The type of abrasive belt used to polish the sheet also has an effect on what applications the polished surface is most suitable for. 240 grit polish is achieved using an aluminium oxide abrasive belt. If you need a polish that cleans very well, e.g. for catering or sanitary purposes, a product polished using a silicon belt is recommended. This is because aluminium oxide polished are rougher than silicon polished. They can create very small pockets where dirt or contaminants can sit. For these kinds of applications please look for ‘240 grit silicon’ in our product descriptions.

Note: Dull polished sheets can vary slight from batch to batch, this is due to the wear levels on the belt when they are polished.

Bright annealed

This product has a reflective finish, almost like the chrome bumper on a car from the 1970’s. It’s not quite a mirror finish but is very bright.

Bright annealed finishes are produced by annealing the stainless steel in an inert atmosphere. This doesn’t allow a surface scale to form. Bright annealed surfaces are still a form of mill finish. This means that the brightness and surface finish can vary from one batch to another. Some sheets can have a slight milky tinge to them, others can have a more pronounced grain.

Ultrabright

Ultrabright is the nearest thing available to a mirror finish in stainless steel. To make this product we take our highest quality 2B sheets and polish them several times to achieve a high level of reflectivity. These sheets are so bright they have been used as mirrors in security sensitive applications such as prisons.

Purchase stainless steel online

Apart from stainless steel, you can also purchase aluminium in our online shop. For further questions, please contact us via our contact form.

Tags Metals