20CrMnSi chemical composition and mechanical properties, main uses Gate Valve,Din Iron Gate Valve,Cast Steel Sealing Gate Valve,Cast Steel Gate Valve Jiangsu Hida Marine Valve Co., Ltd , https://www.haidavalve.com
20CrMnSi
20CrMnSi is a grade of alloy structural steel specified by Chinese national standards. Unified digital code: A24202.
Standard: GB/T 3077-1988
chemical composition:
Carbon C: 0.17~0.23
Silicon Si: 0.90~1.20
Manganese Mn: 0.80 to 1.10
Sulfur S: Allowable residual content ≤0.035
Phosphorus P: Allowable residual content ≤0.035
Chromium Cr: 0.80~1.10
Nickel Ni: Allowable residual content ≤0.030
Copper Cu: Allowable residual content ≤0.030
â—Mechanical properties:
Tensile strength σb (MPa): ≥ 785 (80)
Yield strength σs (MPa): ≥ 635 (65)
Elongation δ5 (%): ≥12
Area shrinkage ψ (%): ≥ 45
Impact work Akv (J): ≥ 55
Impact toughness value αkv (J/cm2): ≥69(7)
Brinell hardness (HBS100/3000) (annealed or high temperature tempered state): ≦207
Sample size: sample blank size is 25mm
Heat treatment specifications and metallographic organization:
Heat treatment specification: quenching 880 ° C, oil cooling; tempering 480 ° C, water cooling, oil cooling.
Metallographic structure: tempered sorbite + acicular ferrite.
Delivery status: delivered by heat treatment (normalizing, annealing or high temperature tempering) or without heat treatment, the delivery status should be stated in the contract.
The main characteristics have high strength and toughness, high rigidity in cold deformation processing, good punching performance, and suitable for cold drawing processes such as cold drawing and cold rolling. Good welding performance, low hardenability, high temper brittleness, generally not used for carburizing or other heat treatment. If necessary, it can also be used after quenching + tempering [2].
Application examples for the manufacture of high-strength welded parts, tough parts with good toughness, and sheet metal stampings, cold-drawn parts, cold-punched parts with a thickness of less than 16 mm, such as large-section chains and chains in mining equipment. Rings, bolts, etc.
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Chemical composition and mechanical properties of 20CrMnSi