I. Basic Material

Item	Technical Parameters
Material Grade	17-4PH
Chinese National Standard Grade	05Cr17Ni4Cu4Nb
UNS Grade	S17400
DIN Grade	1.4542

II. Chemical Composition (Mass Fraction wt%)

C	Si	Mn	P	S	Cr	Ni	Cu	Nb
≤0.07	≤1.00	≤1.00	≤0.040	≤0.030	15.00～17.50	3.00～5.00	3.00～5.00	0.15～0.45

III. Mechanical Properties

Condition	Tensile Strength ≥MPa	Yield Strength ≥MPa	Elongation ≥	Hardness HRC
A (Solution Annealed)	1255	1105	3%	≤38
H900	1310	1180	10%	40–45
H1025	1060	1000	12%	35–39
H1075	1000	865	13%	33–37
H1150	930	725	16%	28–32

IV. Dimensional Accuracy Specifications

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

V. Machining Process & 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

VI. Physical Properties and Surface Quality

Item	Parameter Description
Material Density	7.80 g/cm³
Magnetism	Magnetic
Surface Appearance Quality	Free of cracks, peeling, pinholes, scale, rust and collision dents

VII. Application Scenarios
Hydraulic and pneumatic fittings, valve shaft components, food and medical equipment, aerospace parts, high-strength wear-resistant precision shafts, corrosion-resistant mold fittings, marine engineering structural components.