I. Basic Material

Item	Technical Parameters
Material Grade	30Cr13
Former Grade	3Cr13
Equivalent Grades	SUS420J2, 1.4028, S42080

II. Chemical Composition (mass fraction wt%)

C	Si	Mn	P	S	Cr	Ni
0.26～0.35	≤1.00	≤1.00	≤0.040	≤0.030	12.00～14.00	≤0.60

III. Mechanical Properties

Item	Mechanical Properties
Tensile Strength Rm	≥735 MPa
Yield Strength Rp0.2	≥540 MPa
Elongation after Fracture A	≥12%
Brinell Hardness	217～241 HB

IV. Dimensional Accuracy Specifications

Item	Technical Requirements
Common Diameter Range	φ3.0mm ～ φ300mm
Diameter Tolerance	Standard grade: h8, h9; High precision grade: h7, f7, g6, h6
Roundness	≤1/2 diameter tolerance
Straightness	≤0.10mm/1000mm
Standard Length	φ40mm and below: 3 meters; Above φ40mm: 6 meters available (custom fixed lengths supported)
End Face Requirements	Flat ends, chamfered and deburred

V. Processing Technology & Surface Roughness

Process Type	Complete Process Flow	Surface Roughness
Process 1	Hot rolled base material → Precision drawing → Centerless precision grinding	Ra 0.4～0.8μm
Process 2	Hot rolled base material → Peeling & straightening → Centerless precision grinding	Ra 0.4～0.8μm
Process 3	Hot rolled base material → Peeling & straightening → Centerless precision grinding → Polishing	Ra ≤0.2μm
Process 4	Hot rolled base material → Quenching and tempering → Peeling & straightening → Centerless precision grinding → Polishing	Ra ≤0.2μm
Process 5	Hot rolled base material → Peeling & straightening → Surface quenching → Centerless precision grinding → Polishing	Ra ≤0.2μm

VI. Physical Properties and Surface Quality

Item	Parameter Description
Material Density	7.75 g/cm³
Magnetism	Magnetic
Surface Appearance Quality	Free of cracks, peeling, blowholes, oxide scale, rust and collision dents

VII. Application Scenarios
Pump shafts, valve stems, cutting tools, bearings, medical devices, wear-resistant precision shafts, food processing machinery, wear-resistant and corrosion-resistant structural parts.