How Stainless Steel Is Made & Manufactured

Without the addition of chromium, carbon steel, which is an alloy of iron and carbon, is highly susceptible to corrosion, as its iron content readily oxidises, or rusts, in moist conditions.

Throughout history, since the iron age, many attempt had been made to produce metals that had the strength of iron but that wouldn't corrode over a relatively short period of time. Some attempts were more successful than others. It was formulated in the early 19th century and perfected in the early 20th century, is the best solution so far. In terms of strength, durability and availability, it's the obvious choice for designers and builders of countless products and structures, worldwide.

Just like all steel, is produced by smelting, a process that involves the extraction of iron from iron ore and combining it with a small percentage of carbon, in the case of carbon steel, and with carbon and chromium in the case of stainless steel. Other elements may also be added to further vary the chemical properties of the steel, such as melting point and tensile strength, etc.

By adding eleven percent chromium to normal carbon steel alloy during production, stainless steel is formed. The enhanced resistance to corrosion is a result of the chromium in the alloy reacting with the surrounding atmosphere to form a layer of chromium oxide. This provides a protective shield on the surface of the metal that prevents, or greatly reduces, the destructive oxidising of the iron content of the steel.

Again like most steel it has another useful property. It's recyclable. Recycling is highly cost effective, as it's cheaper than producing new steel from smelting and refining of iron ore. The savings are significant, and steel companies recycle steel as a matter of course. The source material for recycled steel is plentiful, and finds its way to steelmakers, via scrap dealers and recycling centres, who supply it in the form of scrapped cars, washing machines, refrigerators, utilty sinks, cans, construction beams, rail tracks, and countless more discarded steel and iron based products.

Recycled stainless steel has equally effective anti-corrosion properties, but due to residual impurities, certain applications are more suited than others. Basic oxygen steel-making, for example, is a process that uses around thirty percent of recycled steel in its steel production. The greater malleability of this steel finds uses in products such as cans. Recycled stainless steel with greater residual content is less malleable, and is used in heavy construction.