Steel grading systems give us a way to categorize steel types based on all the different uses that make them distinct.
For instance, the rate that manufacturers cool steel can impact how strong it is on a molecular level. The amount of time they keep steel at critical temperatures during the cooling process plays an important role as well. In fact, it’s possible for two sheets of steel with the same alloy content to have different grades based on their heat-treatment process.
- The ASTM Grading System assigns each metal a letter prefix based on its overall category (“A” is the designation for iron and steel materials), as well as a sequentially assigned number that corresponds with that metal’s specific properties.
- The SAE Grading System uses a four-digit number for classification. The first two digits denote the steel type and alloying element concentration, and the last two digits indicate the carbon concentration of the metal.
Steel grading standards are widely used by scientists, engineers, architects, and government agencies to ensure the quality and consistency of materials. These standards provide a common language to communicate the properties of steel with great specificity, and guide product manufacturers toward proper processing and application procedures.