What are stainless steel sheets, and what properties make them so versatile?

Stainless steel sheet is a flat-rolled product manufactured by rolling stainless steel slabs. Depending on the required material thickness, this process involves either hot rolling or cold rolling. While hot-rolled coil often forms the basis for thicker stainless steel plate, cold-rolled sheet offers a smoother surface and tighter tolerances. Compared with standard structural steel or galvanized materials, stainless steel sheet has a chromium content of at least 10.5 %. This enables the formation of a protective passive layer that shields the material from external influences and ensures lasting corrosion resistance.

We supply these sheets in both standard sizes and precision-cut formats. The range extends from thin foil sheets for façade cladding to heavy-gauge plates for heavy engineering. Their versatility stems from the combination of formability, weldability and the visual brilliance achieved through our mechanical and chemical finishing processes. Stainless steel sheets are therefore far more than just raw material; they are functional design elements for the most demanding technical requirements.

Designations and Synonyms – Relevant Standards and Terms Explained

Various designation systems exist to standardize communication between manufacturers, distributors and specifiers. In Europe, the numerical material grade according to DIN EN 10088 is the primary designation, while AISI designations or common names are often used internationally.

V2A and V4A – The Most Common Generic Terms

The designations V2A and V4A are historical terms derived from “Versuchsschmelze 2 Austenit” (test melt 2 austenite). Today, they are used as generic terms for standard stainless steel grades. V2A usually refers to grade 1.4301 (AISI 304) and is suitable for normal environmental conditions in both interior and exterior applications. V4A, by contrast, often refers to grade 1.4404 (AISI 316L) and also contains molybdenum. This increases its resistance to chlorides, making it suitable for use in coastal areas or swimming pools.

AISI Designations – The American Standard

The American Iron and Steel Institute (AISI) uses a three-digit numbering system. The 300 series denotes austenitic stainless steels (e.g. AISI 304, 316), while the 400 series covers ferritic or martensitic grades (e.g. AISI 430). For international projects, we follow these standards to ensure precise material specifications for our overseas and yacht-building customers.

Material numbers according to DIN EN

The material number (e.g. 1.4016) provides the highest level of precision. The first digit, “1”, denotes steel, while the subsequent digits define the chemical group and the specific alloy. For our production in Cleebronn, this standardisation is the binding basis for ensuring reproducible surface quality in every batch.

Chemical Composition

The performance of a stainless steel sheet is determined by its specific alloy. The chemical elements determine how the material responds to mechanical loads or aggressive media.

• Iron (Fe): The base element of the material, forming its crystalline structure.
• Chromium (Cr): At least 10.5% is required for corrosion resistance through the formation of a passive layer.
• Nickel (Ni): Stabilizes the austenitic microstructure and improves toughness and weldability.
• Molybdenum (Mo): Increases resistance to pitting corrosion in chloride-containing environments (typical of V4A).
• Carbon (C): Is deliberately kept low (often < 0.03% in L grades) to prevent intergranular corrosion after welding.
• Manganese (Mn) and silicon (Si): Used for deoxidation and influence the strength of the material during production.

Properties of Stainless Steel Sheets

The physical and mechanical properties vary considerably between the individual grades. We select the base material for our finishing processes precisely according to the required properties of the end product.

Mechanical properties

Stainless steel sheets offer high tensile strength and excellent elongation at break. This combination allows extensive plastic deformation without the material tearing – a key advantage for folded profiles or deep-drawn components. Depending on the alloy and degree of work hardening, the yield strength is significantly higher than that of conventional structural steel.

Physical Properties

Of particular note is the low thermal conductivity compared with aluminium or copper. At the same time, the coefficient of thermal expansion of austenitic steels is relatively high, which must be taken into account when installing large façade areas in architectural applications. The density remains constant at approx. 7.9 to 8.0 kg/dm³.

Corrosion Resistance

This is the key characteristic of the sheets. Through the spontaneous formation of a chromium oxide layer, the surface self-heals minor damage when exposed to oxygen. Grades such as 1.4462 (Duplex) or high-alloy stainless steels such as 1.4547 provide protection in extreme chemical environments or under continuous contact with seawater.

Magnetism

Austenitic sheets (1.4301, 1.4404) are essentially non-magnetic in the annealed condition. However, cold forming, such as bending or press-brake forming, can produce a certain amount of strain-induced martensite, resulting in weak magnetic attraction. Ferritic steels such as 1.4016, by contrast, are inherently magnetic, making them suitable for specific applications in the household appliance industry.

Applications and Industries

The applications for stainless steel sheet are virtually limitless. Our refined finishes are used across a wide range of sectors.

• Architecture and façade construction: Used as large-format panels with mirror-polished or textured finishes for iconic buildings worldwide.
• Elevator construction: Durable and aesthetically pleasing cladding for cabins and doors, often featuring our nanoINOX® anti-fingerprint coating.
• Yacht and shipbuilding: Use of V4A grades for railings, cladding and interiors that withstand salt-laden air over the long term.
• Food and pharmaceutical industries: Smooth, easy-to-clean surfaces for tanks, vessels and worktops that meet the strictest hygiene standards.
• Mechanical and plant engineering: Structural sheet metal for enclosures, protective guards and functional components in harsh production environments.
• Shopfitting and exhibition stand construction: Use of colored PVD/TiN-coated sheets for exclusive brand presentations and durable interior designs.

Overview of international standard designations

For global procurement and planning, equivalencies between the various standards are essential. We supply material that meets the requirements of multiple standards simultaneously.

• 1.4301: Equivalent to AISI 304, X5CrNi18-10, SUS 304 – the standard austenitic grade for general-purpose applications.
• 1.4404: Equivalent to AISI 316L, X2CrNiMo17-12-2, SUS 316L – optimized for corrosion resistance and weldability.
• 1.4016: Equivalent to AISI 430, X6Cr17, SUS 430 – magnetic chromium stainless steel for interior applications.
• 1.4462: Equivalent to AISI 318LN, UNS S31803 – high-strength duplex stainless steel for offshore applications.
• 1.4571: Equivalent to AISI 316Ti – titanium-stabilized stainless steel, traditionally used in German plant and equipment engineering.

Finishing stainless steel sheets – expertise from mirrorINOX

We transform ordinary stainless steel sheets into functional works of art. At our production facility in Cleebronn, we create finishes that meet the highest standards of precision and aesthetics. Our quality management system is certified to ISO 9001, ensuring complete documentation and process reliability. We offer a globally unique range of processes to optimise the physical and visual properties of the base material.

Our proprietary brands include Perfect Mirror No. 10®, a mirror-polished finish that sets new standards in reflectivity and flatness. With our nanoINOX® process, we apply ultra-thin sol-gel-based coatings that provide anti-fingerprint (AFP) or easy-to-clean (ETC) properties. We also use PVD/TiN coating to give sheets a durable colour finish without losing their metallic feel. Our VIBES and BEADS textures give the sheets unique depth through special blasting or grinding processes. Every project benefits from our ability to apply these processes reproducibly to formats up to 16,000 mm in length.