Steel

Steel is the backbone of automotive manufacturing and remains the dominant structural material by volume in most vehicles. It is an iron-carbon alloy (typically 0.02–2.1% carbon) with a wide range of grades engineered for different applications — from deep-drawing quality (DDQ) steels for body panels to advanced high-strength steels (AHSS) for crash structures. Mild and low-carbon steels are used extensively for body panels, floor sections, doors, and structural members due to their excellent formability and weldability. High-strength steels (HSS) and advanced high-strength steels (AHSS) — including dual-phase, martensitic, and transformation-induced plasticity (TRIP) steels — allow engineers to reduce gauge thickness while maintaining or improving crash performance. Steel's dominance in automotive applications stems from its versatility: it can be stamped, welded, roll-formed, hydroformed, and cast with well-established, cost-effective processes. Its high stiffness, energy absorption in crashes, and excellent recyclability make it the benchmark against which alternative materials are measured. While aluminium and carbon fibre are displacing steel in premium and performance vehicles, steel continues to offer the best combination of mechanical performance, cost, and manufacturability for mainstream production.