ASTM A656/A656M Type 3 Grade 550 Introduce
The technical requirements for hot-rolled and cold-formed steel structures are determined by building codes. ASTM A656/A656M is a structural steel standard that defines the properties of structural steel plates, from the tensile strength and yield strength, to the temperature and stress resistance. This standard not only provides the characteristics required for building a strong structure, but it also helps to reduce the cost of the construction by establishing a set of guidelines to be followed.
Smelting temperature:1728°C - 1217°C
Application:High-strength low-alloy hot-rolled structural steel plate with improved forgeability
ASTM A656/A656M Type 3 Grade 550 Material Chemical Composition
The chemical composition of the ASTM A656/A656M Type 3 Grade 550 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Vanadium (V) | - | 0.0800 |
| Silicon (Si) | - | 0.6000 |
| Sulfur (S) | - | 0.0350 |
| PhOsphorus (P) | - | 0.0250 |
| Niobium (Nb) | 0.0080 | 0.1000 |
| Nitrogen (N) | - | 0.0300 |
| Manganese (Mn) | - | 1.6500 |
| Carbon (C) | - | 0.1800 |
ASTM A656/A656M Type 3 Grade 550 Material Mechanical Properties
Yield strength is an indication of a material's ability to resist deformation when subject to an applied stress. Yield strength, measured in ksi, is one of the most important properties of ASTM A656/A656M Type 3 Grade 550 steel. It is the stress at which a piece of the material will no longer continue to elongate in length but will instead deform irreversibly. The minimum specified yield strength for ASTM A656/A656M Type 3 Grade 550 steel is 50 ksi.
The mechanical properties of the ASTM A656/A656M Type 3 Grade 550 steel are as follows:
| YieldRp0.2 | ≤ 889 (MPa) |
| TeileRm | ≤ 185 (MPa) |
| ImpactKV/Ku | 41(J) |
| ElongationA | 42% |
| Reduction in cross section on fractureZ | 32% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 211 |
ASTM A656/A656M Type 3 Grade 550 Material Thermal Properties
The thermal performance parameters of the ASTM A656/A656M Type 3 Grade 550 steel are as follows:
| Temperature (°C) | 23 | 323 | 754 |
| Modulus of elasticity (GPa) | - | 227 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 33 |
| Thermal conductivity (W/m·°C) | - | 43.3 | 24.2 |
| Specific thermal capacity (J/kg·°C) | - | 231 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.41 | - | - |
| Deity (kg/dm³) | - | - | 334 |
| Poisson’s coefficient, ν | - | - | 314 |
ASTM A656/A656M Type 3 Grade 550 Material Machining Technology
The cutting parameters for machining ASTM A656/A656M Type 3 Grade 550 steel should be optimized for the specific application, based on the tool material and geometry being used. Generally, cutting speed should be kept between 30 and 100 m/min, and feed rate should range from 0.05 to 0.4 mm/tooth. These parameters should be adjusted depending on the type of operation being performed.