I. Basic Material

Item	Technical Parameters
Base Material Grade	2205 Duplex Stainless Steel
GB Standard Grade	022Cr22Ni5Mo3N
UNS Grade	S32205
DIN Grade	1.4462
Surface Treatment	Chrome Plated
Chrome Plated Coating Thickness	Diameter ≤φ20: 15μm; Diameter＞φ20: 20μm, customizable thickness as required
Surface Hardness after Chrome Plated	HV800～1100
Common Diameter Range	φ3.0mm～φ300mm
Diameter Tolerance	Conventional grades: h8, h9; High-precision grades: h7, f7, g6, h6
Roundness	≤1/2 of diameter tolerance
Straightness	≤0.10mm/1000mm
Standard Length	Fixed length of 3 meters for φ40mm and below; fixed length of 6 meters for diameters above φ40mm, customized fixed lengths available for large specifications
End Face Requirements	Flat ends with chamfering and burr removal

II. Chemical Composition of Base Material (Mass Fraction wt%)

C	Si	Mn	P	S	Cr	Ni	Mo	N
≤0.030	≤1.00	≤2.00	≤0.030	≤0.020	21.00～23.00	4.50～6.50	2.50～3.50	0.14～0.20

III. Mechanical Properties

Item	Mechanical Properties
Tensile Strength Rm	≥620 MPa
0.2% Proof Strength Rp0.2	≥450 MPa
Elongation after Fracture A	≥25%
Base Material Hardness	≤293 HB

IV. Processing Technology & Surface Roughness

Process Type	Complete Process Flow	Surface Roughness
Process 1	Hot-rolled base material → Precision drawing → Centerless precision grinding → Polishing → Chrome Plated → Secondary polishing	Ra ≤0.2μm
Process 2	Hot-rolled base material → Peeling & straightening → Centerless precision grinding → Polishing → Chrome Plated → Secondary polishing	Ra ≤0.2μm
Process 3	Forged round bar → Turning finishing → Centerless precision grinding → Polishing → Chrome Plated → Secondary polishing	Ra ≤0.2μm

V. Coating & Physical Characteristics

Item	Parameter Description
Coating Adhesion	No peeling or flaking; qualified by bending resistance test
Corrosion Resistance	The duplex steel substrate features excellent anti-corrosion performance; combined with composite Chrome Plated protection, it resists chloride ions, acids, alkalis and pitting corrosion
Coefficient of Friction	Dense and smooth surface layer with low friction coefficient, high wear resistance and scratch resistance
Magnetism of Base Material	Magnetic (attributed to duplex microstructure)

VI. Application Scenarios
Seawater desalination equipment, marine engineering, flue gas desulfurization and denitrification equipment, high-chloride chemical working conditions, high-strength anti-corrosion piston rods, corrosion-resistant valve stems, heavy-load precision anti-corrosion transmission shaft parts.