PH 15-7 Mo precipitation Hardening Stainless Steel (AMS 5520/ UNS S15700)

PH 15-7 Mo is a semi-austenitic precipitation-hardening stainless steel used for applications requiring high strength and moderate corrosion resistance. It is similar to 17-7 with the substitution of 2% Molybdenum for 2% Chromium resulting in higher room and elevated temperature strength for 15-7 Mo. PH 15-7 Mo stainless steel may be formed in a soft austenitic condition and then hardened to high strength levels by low temperature heat treatments. This allows miminum distortion compared to other quench and temper hardening processes. For maximum strength requirements, 15-7 Mo strip can be supplied in the hard-rolled Condition C for heat treatment to condition CH900.

Solution Treatment: heat to 1950°F and air cool

Solution Treatment: heat to 1950°F and air cool

Austenite Condition: Heat to 1400°F and hold for 90 minutes and cool to 55°F within 1 hr and hold for 30 minutes

Precitipation Harden: Heat to 1050°F and hold for 90 minutes then air cool

Solution Treatment: heat to 1950°F and air cool

Austenite Condition: Heat to 1750°, hold for 10 minutes and cool to room temperature. Then within 1 hour cool to -100°F, hold for 8 hours then warm in air to room temperature

Precitipation Harden: Heat to 950°F and hold for 90 minutes then air cool

Condition C: Condition A is transformed to martensite at the mill by cold reduction to Condition C

Precipitation Harden: Heat to 900°F (+/-10) and hold for 60 minutes then air cool

Properties:Annealed

Ultimate Tensile Strength: 150 KSI max (1035 MPa max)

Yield Strength (0.2% offset): 55 KSI max (380 MPa max)

Elongation:20% min

Hardness:Rb 92 max

Type PH 15-7 Mo can be cold rolled to various tempers. Contact Ulbrich Technical Service for additional information.

Ultimate Tensile Strength: 200 KSI min (1380 MPa min)

Yield Strength (0.2% offset): 175 KSI min (1205 MPa min)

Elongation:1 % min

Hardness:Re 41 min

Corrosion resistance of Type PH 15-7 Mo stainless steel in Conditions TH 1050 and RH 950 is superior to that of the standard hardenable chromium types of stainless steels such as Types 410, 420 and 431, but is not quite as good as chromium nickel type 304.