20Cr alloy structure steel stockholders and suppliers from china. OTAI SPECIAL STEEL Supply in GB 20Cr steel round bar, plate, sheet, square bar, flat bar, pipe since 2007.our steel stock more 1000tons

GB 20Cr alloy Steel is a high quality Quenched and Tempered Alloy Structural steel, It belong to the high quality low carbon,Low alloy chromium, molybdenum, nickel case hardening steel. Oil Quenched & Tempered Hardness is 28-34 HRc. GB 20Cr steel Annealing delivery hardenss less than 250HB.20Cr With a lower carbon content range, So GB 20Cr alloy steel have good weldability.

Related Specifications ASTM A29/A29M DIN EN 10083/3 JIS G4053 GB/T 3077

Form of Supply

GB 20Cr Alloy steel, we can supply the round bar, steel flat bar, plate, hexagonal steel bar and steel square block. GB 20Cr steel Round bar can be sawn to your required lengths as one offs or multiple cut pieces. 20Cr alloy steel Rectangular pieces can be sawn from flat bar or plate to your specific sizes. Ground tool steel bar can be supplied, providing a quality precision finished bar to tight tolerances.

Chemical composition

C(％) 0.18～0.24 Si(％) 0.17～0.37 Mn(％) 0.50～0.80 P(％) ≤0.030
S(％) ≤0.030  Cr(％) 0.70～1.10

Equivalent Of 20Cr alloy Structure Steel

USA Germany China Japan France England Italy Poland ISO Austria Sweden Spain
ASTM/AISI/UNS/SAE DIN,WNr GB JIS AFNOR BS UNI PN ISO ONORM SS UNE
5120 / G51200  20Cr4 / 1.7027 20Cr SCr420  18C3  527A20 20Cr4

Heat treatment Related

  • Annealing of 20Cr Alloy structural steel

Slowly heated to 850 ℃ and allow enough times, let the steel to be thoroughly heated, Then cool slowly in the furnace. The 20Cr alloy steel will get MAX 250 HB （Brinell hardness）.

  • Hardening of GB Alloy structural steel 20Cr

First quenching heated slowly to 880°C, Then after adequate soaking at this temperature quench in oil or water. Temper as soon as tools reach room temperature. Second quenching heat to 780-820°C， then quenching in oil or water.

  • Tempering of 20Cr Alloy structural steel

Heat to 20°C, then cool in water or oil.normal delivery hardness 179HB Min.

Mechanical Properties

The mechanical properties of annealed GB 20Cr alloy steel are outlined in the table below

Tensile strength Yield strength Elongation Reduction of area Poisson’s ratio Impact absorbing energy
σb/MPa σs/MPa δ5(％) ψ(％) AKV/J
835 540 10 min 40 min 0.27-0.30 47 Min

Applications

GB 20Cr steel is widely used for a variety of applications in the used in the automotive and engineering industries for toolholders and other such components. Mostly used in the manufacture of the demand is higher, intensity of heart surface wear, under section under 30 mm or small carburized parts of complex shape and load (oil quenching), such as: transmission gear, gear shaft, CAM, worm, piston pin, claw clutch, etc.; For the heat treatment deformation and high abrasion resistance parts, should be high frequency surface quenching after carburizing, such as modulus is less than 3 of the gear, shaft, spline shaft, etc. This steel can be used in the quenched and tempered state and used in the manufacture of large and medium under impact load in her work parts, this kind of steel also can be used as a low carbon martensite steel quenching, further increasing steel yield strength and tensile strength increased (about 1.5 ~ 1.7 times). Typical applications such as valve bodies, pumps and fittings, Shaft, the high load of wheel, bolts, double-headed bolts, gears, etc

Regular size and Tolerance

Steel round bar: Diameter Ø 5mm – 3000mm

Steel plate: Thickness 5mm – 3000mm x Width 100mm – 3500mm

Steel Hexagonal bar: Hex 5mm – 105mm

Others 20Cr have not specified size, pls contact our experienced sales team.

Processing

GB 20Cr alloy steel round bar and flat sections can be cut to your required sizes. 20Cr alloy steel ground bar can also be supplied, providing a high quality tool steel precision ground tool steel bar to your required tolerances. GB 20Cr steel is also available as Ground Flat Stock / Gauge Plate, in standard and nonstandard sizes.

Contact our experienced sales team to help you with your 20Cr alloy steel questionsadn enquiry by Email or Telphone. The questions will be reply in 24 hours.

OTAI SPECIAL STEEL CO., LTD

Email: jack@otaisteel.com   TEL: 0086-769-33232622   FAX: 0086-769-88705839