What is Stainless Steel & How Stainless Steel is Made?

Understanding the creation of stainless steel is pivotal in appreciating its role in our daily lives. It’s a material heralded for its strength and resistance to corrosion, making it indispensable across various industries. National Stainless Steel Centre (NSSC) stands at the forefront of providing premium stainless steel solutions, combining precision technology and comprehensive experience to meet your specific needs.

Process of how stainless steel is made.
To make stainless steel, the raw materials—iron ore, chromium, silicon, nickel, etc.—are melted together in an electric furnace. This step usually involves 8 to 12 hours of intense heat. Next, the mixture is cast into one of several shapes, including blooms, billets, and slabs.

The Composition of Stainless Steel

At its core, stainless steel is an alloy comprised predominantly of iron, infused with chromium—at least 10.5% to be precise—which bestows it with its renowned resistance to rust. NSSC takes pride in supplying a variety of stainless steel grades, including locally manufactured 304L and 316L, as well as the robust 3CR12, catering to bespoke requirements through a vast selection of plates, coils, and tubes.

HOW STAINLESS STEEL IS MADE


The production path of a specific grade of stainless steel can vary during the final phases. The shaping, processing, and finishing of the steel grade profoundly influence its appearance and functionality. To produce a finalized steel product, the initial step involves forming the molten alloy. This is why the beginning stages of manufacturing are generally uniform across various steel grades.

Stainless steel is renowned for its corrosion resistance and strength, attributes that are determined by the specific process of creation and finishing applied to each grade of steel.

Stainless steel Composition
Stainless steel Composition

Commencing the Production

The initial phase in stainless steel manufacturing is the formation of a molten alloy, involving a series of shared steps across different steel grades.

Step 1: Melting

The journey begins by melting scrap metals and additives in an electric arc furnace (EAF), where high-power electrodes heat the metals to create a molten mixture. This process utilizes recycled steel, up to 60%, which is not only cost-effective but also environmentally considerate.

Step 2: Carbon Content Reduction

The strength and hardness of iron are enhanced by carbon, but an excess can lead to complications. Carbon content calibration is critical, employing Argon Oxygen Decarburization (AOD) or Vacuum Oxygen Decarburization (VOD) to achieve the desired levels, providing precise control over the final product’s characteristics.

Step 3: Tuning

Post-carbon reduction, the steel undergoes a balancing of temperature and chemistry to ensure consistency and adherence to the intended grade’s requirements, with adjustments made as needed based on testing and analysis.

Step 4: Forming or Casting

The molten steel is then shaped into primitive forms, such as blooms, billets, slabs, rods, and tubes, each marked for tracking through subsequent processes. These forms are then processed further depending on their final use, with some going through additional steps to acquire the necessary appearance and characteristics.

stainless steel finish
stainless steel finish

Further Processing

The steel, now in a rough shape, is subjected to hot rolling, which sets its initial dimensions. For more precision, cold rolling is employed, often necessitating further heat treatment. The annealing process follows, softening the steel and relieving stress.

Surface Treatment

Surface scale accumulation is an inevitable part of processing, affecting the steel’s appearance and properties. Descaling or pickling is essential in maintaining stainless steel’s resistance to corrosion and stain, achieved through acid baths or controlled heating and cooling.

Finalisation of Steel

The steel is cut to meet specific order requirements, using various mechanical or more sophisticated methods for complex shapes. Finally, the steel is finished to the customer’s preference, ranging from matte to mirror, and prepared for delivery.

Quality Control and Customization

NSSC’s experienced staff and advanced technology are not just about adhering to standards but pushing the envelope of innovation. Our products undergo rigorous quality control, tailored to the unique demands of sectors from agriculture to automotive. With NSSC, you’re assured of a product that’s not just made but crafted to perfection.

NSSC: A Hub of Precision

Strategically located in Kempton Park, Gauteng, NSSC is positioned to serve a global clientele, offering services that span laser cutting, CNC bending, and even pre-fabrication. Our three decades of industry experience fuel our vision for the future of stainless steel in South Africa and beyond.

Stainless steel’s journey from raw elements to a finished product is complex yet fascinating. NSSC harnesses this process, offering you a product that’s not only built to last but also crafted to the highest standards of precision and quality. Whether you require stainless steel for construction, petrochemical applications, or bespoke architectural designs, trust NSSC to deliver with excellence.

NSSC isn’t just a supplier; we’re innovators, dedicated to propelling the stainless steel industry forward, ensuring that when you ask “How is stainless steel is made?” you’re not just getting an explanation but a comprehensive solution tailored just for you.