PH 13-8Mo (UNS S13800 / W.Nr. 1.4534)

PH 13-8Mo (UNS S13800 / W.Nr. 1.4534) is a martensitic precipitation/age-hardening stainless steel capable of high strength and hardness along with good levels of resistance to both general corrosion and stress-corrosion cracking. In addition, the alloy exhibits good ductility and toughness in large sections in both the longitudinal and transverse directions. The excellent properties of PH 13-8 Mo stainless are obtained through close control of chemical composition and microstructure plus specialized melting which reduces impurities and minimizes segregation. Compared to other ferrous-based materials, this alloy offers a high level of useful mechanical properties under severe environmental conditions.

Equivalent Grades

PH 13-8MoXM-13S13800X3CrNiMoAl13-8-21.4534

Chemical Composition, %

PH 13-8Mo≤0.05≤0.10≤0.10≤0.01≤0.00812.25-13.257.5-8.52.0-2.5≤0.01Bal

Typical Physical and Mechanical Properties (RT, Annealed)

Density, g/cm3Melting Point, ℃Tensile Strength, MPaYield Strength, MPaELongation, %Hardness, HRB

Available Products and Specifications

Rod, Bar, Wire and ForgingsASTM A564, 705, SAE AMS 5629
Plate, Sheet and StripASTM A693, SAE AMS 5604
Pipe and Tube
Welding Product


PH 13-8 Mo stainless has good fabrication characteristics and can be age-hardened by a single low temperature treatment. Cold work prior to aging increases the aging, especially for lower aging temperatures.


PH 13-8 Mo stainless has been used for valve parts, fittings, cold-headed and machined fasteners, shafts, landing gear parts, pins, lockwashers, aircraft components, nuclear reactor components and petrochemical applications requiring resistance to stress-corrosion cracking. Generally, this alloy should be considered where high strength, toughness, corrosion resistance, and resistance to stress-corrosion cracking are required in a steel showing minimal directionality in properties.