Stainless Steel:How is it made?


Stainless steel is well known for its excellent corrosion resistance, and is used in a large variety of appliances ranging from kitchenwares to surgical tools and buildings. Stainless steel is an iron alloy with added elements, the most important of which is chromium, because it gives stainless steel its anti corrosive properties. 


Making stainless steel requires a series of processes. The first step is melting, often done by mixing raw materials in an electric arc furnace in intense heat for 10 to 12 hours. The molten steel is then cast into semi finished forms, usually in a rectangular or cylindrical shape. The outputs are blooms, billets, and slabs.


The next step is forming. The steel goes through “hot rolling”, as it is heated and passed through large rolls. At the end of this stage, blooms and billets are formed into bar and wire, while slabs are formed into plate, strip, and sheet.


The next step is a heated phase in which the formed steel is annealed to relieve internal stresses and to soften the metal. Some steels go through “age hardening”, where higher temperatures mean lower strength but higher toughness. Certain rapid cooling treatments are used to increase toughness without compromising much strength. This step requires careful control because any small change in the temperature or cooling rate can seriously affect the metal’s properties. The type of heat treatment depends on the type of steel.


Annealing causes scale or build up to accumulate on the metal, thus the next step, descaling, is removing this built up scale. There are several methods of descaling, from using a nitric-hydrofluoric acid bath (pickling), to applying an electric current to the metal’s surface in combination with a cathode and phosphoric acid (electrocleaning).


The next step is cutting the stainless steel to the desired size. Cutting also uses a variety of methods, some being straight and circle shearing, high speed steel blade sawing, using metal punches (blanking).


The final step is finishing. The type of finishing depends on the desired use of the stainless steel. Soft finishes are easier to clean and rough finishes are often required for lubrication applications.


SMC we offer a wide variety of stainless steel products of the highest quality, such as stainless steel pipe, wire, sheet, and mesh. Our items are packaged according to regulation and to your individual requirements. All of our products are carefully labeled with the product ID and quality information. For more information including product specifications and price, please click here.