ASTM A573/A573M Grade Gr70 Introduce
The ASTM A573/A573M steel standard is a new specification developed by the American Society for Testing and Materials (ASTM) International, which sets out requirements for structural steel plates produced to A573/A573M specification. This standard is the result of an effort of an international industry group that has focused on the proper materials design, selection and use of these structural steel plates. It has been created in response to the industry's need for uniform industry-wide guidelines and requirements for the design, fabrication, and use of A573/A573M steel.
Smelting temperature:1162°C - 1218°C
Application:Structural carbon steel plate for enhancing toughness
ASTM A573/A573M Grade Gr70 Material Chemical Composition
The chemical composition of the ASTM A573/A573M Grade Gr70 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Carbon (C) | 0.2400 | 0.2600 |
| Manganese (Mn) | 0.8500 | 1.2000 |
| PhOsphorus (P) | - | 0.0350 |
| Sulfur (S) | - | 0.0400 |
| Silicon (Si) | 0.1500 | 0.4000 |
ASTM A573/A573M Grade Gr70 Material Mechanical Properties
In order to classify ASTM A573/A573M steels, they are divided into four groups based on the mechanical properties they possess. These groups are identified as follows: Group I steels have higher minimum astm-specified values for yield and tensile strength; Group II steel contains improved formability and weldability; Group III steels have improved toughness; and Group IV steel has improved atmospheric corrosion resistance.
The mechanical properties of the ASTM A573/A573M Grade Gr70 steel are as follows:
| YieldRp0.2 | ≤ 283 (MPa) |
| TeileRm | ≤ 863 (MPa) |
| ImpactKV/Ku | 14(J) |
| ElongationA | 34% |
| Reduction in cross section on fractureZ | 32% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 143 |
ASTM A573/A573M Grade Gr70 Material Thermal Properties
The thermal performance parameters of the ASTM A573/A573M Grade Gr70 steel are as follows:
| Temperature (°C) | 21 | 752 | 465 |
| Modulus of elasticity (GPa) | - | 563 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 43 |
| Thermal conductivity (W/m·°C) | - | 23.3 | 24.2 |
| Specific thermal capacity (J/kg·°C) | - | 113 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.31 | - | - |
| Deity (kg/dm³) | - | - | 111 |
| Poisson’s coefficient, ν | - | - | 114 |
ASTM A573/A573M Grade Gr70 Material Machining Technology
ASTM A573/A573M Grade Gr70 shows good weldability, with excellent machinability and wetability properties. It can be welded by many of the traditional methods, such as shielded metal arc welding (SMAW), gas metal arc welding (GMAW), flux-cored arc welding (FCAW), and submerged arc welding (SAW). It can also be joined using oxy-fuel welding (OFW), or resistance welding, though care must be taken to ensure the temperature of the weld is well controlled.