As the role of tungsten chromium vanadium, this steel has a good warm room temperature mechanical properties and extraordinary high hardenability, tempering good stability, good thermal processing performance. Used in the quenched state, as the working temperature ≤ 500 ℃ heat below the spring, the main valve spring, such as boiler, turbine steam seal springs and so on.

Chemical composition:


Carbon C: 0.26 ~ 0.34


Si Si: 0.17 ~ 0.37


Manganese Mn: ≤ 0.40


Sulfur S: ≤ 0.030

 


        Phosphorus P: ≤ 0.030


Chromium Cr: 2.00 ~ 2.50


Ni-Ni: ≤ 0.35


Copper Cu: ≤ 0.25


Vanadium V: 0.50 ~ 0.80


Tungsten W: 4.0 ~ 4.5

Mechanical properties:


Tensile strength σb (MPa): ≥ 1470 (150) '


Conditions yield strength σ0.2 (MPa): ≥ 1323 (135)


Elongation δ5 (%): ≥ 7


Reduction of area ψ (%): ≥ 40


Hardness: hot heat, ≤ 321HB; cold drawing heat treatment, ≤ 321HB


Note: In addition to tensile strength, the other performance parameters of the test results for reference


Sample size:,


● Heat treatment and microstructure specifications:


Standard heat treatment: quenching 1050 ~ 1100 ℃, oil cooling; tempering 600 ℃ ± 50 ℃ (extraordinary need, ± 30 ℃).