LOW CARBON STEEL
Also known as mild steel, low carbon steel has low strength relative to steel with higher carbon levels. Low carbon steel is the most ductile – or machinable – type of carbon steel as well.
Chemical alloys can also be added to low carbon steel to enhance desired properties without increasing the material’s weight. For example, if low carbon steel requires greater hardness for its desired application, manganese can be added to increase hardness without adding weight. Low carbon steel that contains additional alloys is typically referred to as high strength, low alloy (HSLA) steel.
Some of the most common low carbon steel plate grades, all stocked by Teshi, include ASTM A36, A527 Grades 42 & 50 and A830-1020. Each of these grades have moderate strength, high ductility and lighter weight due to the low carbon content and addition of other alloys. These properties make low carbon steel ideal for use in structural applications like building construction, bridges and transmission towers, where materials must be able to withstand high stress while also being easy to form into structural shapes.
Chemical Composition of Common Low Carbon Plate Grades
GRADE | CARBON | MANGANESE | PHOSPHORUS | SULFUR | SILICON |
A36 UP TO 3/4” THICK | 0.25% | N/A | 0.030% | 0.030% | 0.40% |
A36 >3/4 – 1 ½” THICK | 0.25% | 0.80-1.20% | 0.030% | 0.030% | 0.15-0.40% |
A36 > 1 ½ – 2 ½” THICK | 0.26% | 0.80-1.20% | 0.030% | 0.030% | 0.15-0.40% |
A36 >2 ½ – 4” THICK | 0.27% | 0.85-1.20% | 0.030% | 0.030% | 0.15-0.40% |
A36 >4” THICK | 0.29% | 0.85-1.20% | 0.030% | 0.030% | 0.15-0.40% |
A572 GRADE 42 | 0.21% | 1.35% | 0.030% | 0.030% | 0.15-0.40% |
A572 GRADE 50 | 0.23% | 1.35% | 0.030% | 0.030% | 0.15-0.40% |
A830 GRADE 1020 | 0.18-0.23% | 0.30-0.60% | 0.030% | 0.030% | N/A |
Mechanical Properties of Common Low Carbon Plate Grades
GRADE | YIELD POINT | TENSILE |
A36 | 36 KSI | 58-80 KSI |
A572 GRADE 42 | 42 KSI | 60 KSI |
A572 GRADE 50 | 50 KSI | 65 KSI |
