JIS G3115 SPV235 Introduce
This steel is produced by thermo-mechanical control processing (TMCP) as indicated by the "G" in its name (G3115). This process involves a complete thermal cycle involving hot-rolling, reheating, cooling and quenching in cool water, followed by self-tempering reheating (leveling). With tempered rolling, the surface of the plates achieves more uniform flatness and hardness, better inter-laminar strength in the case of un-alloyed steels, and improved homogeneity, texture, and fusion of lamellar pearlite in the thickness direction, producing an overall uniform product in strength, micro-structure and spheroidized carbides.
Smelting temperature:1887°C - 1199°C
Application:Pressure vessel steel plate used at medium temperature
JIS G3115 SPV235 Material Chemical Composition
The chemical composition of the JIS G3115 SPV235 steel are as follows:
| Element | Min | Max |
|---|---|---|
| Silicon (Si) | - | 0.3500 |
| Sulfur (S) | - | 0.0300 |
| PhOsphorus (P) | - | 0.0300 |
| Manganese (Mn) | - | 1.4000 |
| Carbon (C) | - | 0.1800 |
JIS G3115 SPV235 Material Mechanical Properties
JIS G3115 steels are made of low-carbon-manganese-molybdenum-chromium alloys and have superior mechanical properties such as high yield and tensile strengths, good fatigue strength and impact toughness. They also have excellent cold formability and weldability properties. These steels are ideal for applications such as pressure vessel production, shipbuilding, and construction.
The mechanical properties of the JIS G3115 SPV235 steel are as follows:
| YieldRp0.2 | ≤ 293 (MPa) |
| TeileRm | ≤ 325 (MPa) |
| ImpactKV/Ku | 34(J) |
| ElongationA | 31% |
| Reduction in cross section on fractureZ | 33% |
| As-Heat-Treated Condition | Solution and Aging, Annealing, Ausaging, Q+T,etc |
| Brinell hardness (HBW) | 414 |
JIS G3115 SPV235 Material Thermal Properties
The thermal performance parameters of the JIS G3115 SPV235 steel are as follows:
| Temperature (°C) | 23 | 423 | 991 |
| Modulus of elasticity (GPa) | - | 631 | - |
| Mean coefficient of thermal expaion ×10-6/(°C) | - | - | 22 |
| Thermal conductivity (W/m·°C) | - | 12.3 | 23.2 |
| Specific thermal capacity (J/kg·°C) | - | 124 | - |
| Specific electrical resistivity (Ω mm²/m) | 0.31 | - | - |
| Deity (kg/dm³) | - | - | 432 |
| Poisson’s coefficient, ν | - | - | 423 |
JIS G3115 SPV235 Material Machining Technology
Using a coolant when machining JIS G3115 SPV235 steel can help to improve the cutting performance and reduce the risk of tool breakage and overheating. A good water-soluble coolant, such as a cutting oil, should be used. When tapping, a lubricant should be applied to the tap to reduce friction, improve surface finish, and minimize tap breakage.