15-5PH AMS 5659

15-5 PH stainless steel is a martensitic precipitation-hardening stainless steel which maintains a high strength to approximately 600 °F.  Compared to 17-4 PH, it offers better transverse toughness and ductility: better mechanical properties in larger cross-sections, and better forgeability.

Common stock sizes: .500” to 8” diameters.

Common Specifications:

  • AMS 5659 TYPE 1
  • Pratt & Whitney LCS F-17
  • General Electric S-400 / S-SPEC-35
  • ASTM-A484
  • ASTM-A564; CAP. OF H900
  • ASME-SA564; CAP. OF H900

Common Applications:

  • Aerospace structural components
  • Shafts and gears
  • Fasteners
  • Valves

Industry Trade Names:

  • XM-12
  • 15-Cr-5Ni
  • UNS S15500

Macrostructure Limits:

Class Condition Severity
1 Freckles A
2 White Spots A
3 Radial Segregation A
4 Ring Pattern B

As solution treated the tensile strength shall not exceed 175 ksi and hardness shall not exceed 363 HB.

Rockwell-Industries-Intl-15-5PH-image

Composition

Element Min. Max.
Carbon -- 0.07
Manganese -- 1.00
Silicon -- 1.00
Phosphorus -- 0.030
Sulfur -- 0.015
Chromium 14.00 15.50
Nickel 3.50 5.50
Molybdenum -- 0.50
Copper 2.50 4.50
Columbium (Niobium) 5xC 0.45

Bars shall be solution heat treated in accordance with AMS-H-6875 by heating to 1900 °F ± 25 °F, holding at heat for a time commensurate with section thickness, heating equipment, and procedure used, and cooling as required to below 90 °F.

AMS 5659 Type 1 = VAR melting process
AMS 5659 Type 2 = ESR melting process

The precipitation heat treat requirements are as follows:

Condition Temperature Time
H900 900 °F ± 10 °F (482 °C ± 6°C) 1 hour + 15/-0 minutes
H925 925 °F ± 10 °F (496 °C ± 6°C) 4 hours + 30/-0 minutes
H1025 1025 °F ± 10 °F (552 °C ± 6°C) 4 hours + 30/-0 minutes
H1075 1075 °F ± 10 °F (579 °C ± 6°C) 4 hours + 30/-0 minutes
H1100 1100 °F ± 10 °F (593 °C ± 6°C) 4 hours + 30/-0 minutes
H1150 1150 °F ± 10 °F (621 °C ± 6°C) 4 hours + 30/-0 minutes

Minimum tensile properties in precipitation heat treated conditions:

Minimum tensile strength properties, inch/pound units

Condition Specimen Orientation Tensile Strength ksi Yield Strength at 0.2% Offset ksi Elongation in 2 inches or 4D % Reduction of Area %
H900 Longitudinal
Transverse
190
190
170
170
10
6
35
20
H925 Longitudinal
Transverse
170
170
155
155
10
7
38
25
H1025 Longitudinal
Transverse
155
155
145
145
12
8
45
32
H1075 Longitudinal
Transverse
145
145
125
125
13
9
45
33
H1100 Longitudinal
Transverse
140
140
115
115
14
10
45
34
H1150 Longitudinal
Transverse
135
135
105
105
16
11
50
35