Understanding Common Steel Grading Systems (ASTM, DIN, JIS, GB)

Understanding Common Steel Grading Systems (ASTM, DIN, JIS, GB)

Navigating the world of steel can be complex, with different countries and regions using their own grading systems. Understanding these standards is crucial for selecting the right material for your project. Here’s a simple guide to the most common steel grading systems.

ASTM (American Society for Testing and Materials)
Widely used in North America and many international projects, ASTM standards often use a letter-prefix followed by a number. For example, A36 is a common carbon steel for structural shapes and plates, while A572 denotes high-strength low-alloy steel. The "A" prefix typically refers to ferrous metals.

DIN (Deutsches Institut für Normung)
The German standard, influential across Europe. Many DIN standards have been incorporated into the broader EN (European Norm) system. A classic DIN grade is 1.4301, which is the equivalent of AISI 304 stainless steel. The numbers precisely define the chemical composition.

JIS (Japanese Industrial Standards)
Common in Asia and for automotive components. JIS grades often start with a letter indicating the category (e.g., 'S' for Steel), followed by numbers for tensile strength or other properties. SS400 is a general structural steel, and SPHC is a commercial-quality hot-rolled steel sheet.

GB (Guobiao - Chinese National Standards)
Essential for sourcing from China. A common grade is Q235, where "Q" stands for Yield Strength and "235" indicates a minimum yield strength of 235 MPa. Another is 45# steel, a carbon steel with about 0.45% carbon content.

Why This Matters for Your Business
Understanding these systems ensures you get the precise steel you need and helps in finding equivalent grades across different standards, providing flexibility in sourcing.

At Ruixiang Steel, we are experts in all major grading systems. We help our clients navigate these specifications to source the perfect material, ensuring quality, compliance, and performance for every application, anywhere in the world.