ASTM A307: The Industry Standard for Carbon Steel Fasteners ASTM A307 is a widely used specification for . Known as a "general-purpose" or "run-of-the-mill" fastener standard, it covers diameters ranging from 1/4" to 4" . While it doesn't offer the high-strength performance of structural grades like A325, its versatility and cost-effectiveness make it the backbone of mechanical and construction projects. The Three Grades of A307
: In high-load structural steel applications, A325 bolts are preferred because they offer nearly double the tensile strength of an A307 Grade A bolt. Common Applications a307 material
If a manufacturer’s mark is used, it must be distinct from the grade symbol. ASTM A307: The Industry Standard for Carbon Steel
Next time you grab a standard zinc bolt at the supply house, you’re likely holding A307. The Three Grades of A307 : In high-load
| Element | Grade A | Grade B | Grade C | |---------|---------|---------|---------| | Carbon (max) | 0.29% | 0.29% (low carbon) / 0.49% (med carbon) | 0.29% | | Manganese | 0.60–0.90% | 0.60–0.90% | 0.60–0.90% | | Phosphorus (max) | 0.04% | 0.04% | 0.04% | | Sulfur (max) | 0.05% | 0.05% | 0.05% |