ASTM A387/A387M Grade 12 Class 1 Introduce
ASTM A387/A387M is a standard that covers chromium-molybdenum alloy steel plates intended primarily for welded boilers and pressure vessels designed for elevated temperature service. Commonly referred to as chrome-moly steel, the composition of this alloy includes a high percentage of chromium, molybdenum and other alloying elements, such as vanadium and nickel, all of which contribute to the high strength and hardness of the plates. ASTM A387/A387M is a widely used steel standard for a variety of industries, including but not limited to the chemical, fabrication, construction and industrial process industries.
Smelting temperature:1425°C - 1225°C
Application:Pressure vessel plate, alloy steel, chrome molybdenum
ASTM A387/A387M Grade 12 Class 1 Material Mechanical Properties
ASTM A387/A387M Grade 12 Class 1 steel has very good corrosion resistance. This material can resist the effects of most acids and bases, as well as most saline metal environments. The corrosion resistance of ASTM A387/A387M Grade 12 Class 1 steel makes it an ideal choice for applications in marine and other corrosive environments.
The mechanical properties of the ASTM A387/A387M Grade 12 Class 1 steel are as follows:
| YieldRp0.2 | ≤ 327 (MPa) |
| TeileRm | ≤ 227 (MPa) |
| ImpactKV/Ku | 23(J) |
| ElongationA | 42% |
| Reduction in cross section on fractureZ | 34% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 411 |
ASTM A387/A387M Grade 12 Class 1 Material Thermal Properties
The thermal performance parameters of the ASTM A387/A387M Grade 12 Class 1 steel are as follows:
| Temperature (°C) | 33 | 314 | 538 |
| Modulus of elasticity (GPa) | - | 982 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 33 |
| Thermal conductivity (W/m·°C) | - | 13.3 | 14.2 |
| Specific thermal capacity (J/kg·°C) | - | 214 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.12 | - | - |
| Deity (kg/dm³) | - | - | 323 |
| Poisson’s coefficient, ν | - | - | 344 |
ASTM A387/A387M Grade 12 Class 1 Material Machining Technology
Using a coolant is a must when machining ASTM A387/A387M Grade 12 Class 1 steel. This helps to keep the cutting tools cool and lubricated, both of which increase their lifespan. When selecting a cutting speed, it is important to use a slower one than is recommended for other metal alloys, as this can help minimize tool wear. Sharpening the cutting tools regularly is also beneficial, as this ensures the best results and reduces the risk of premature wear.