Project Description

17-4PH (UNS S17400)

* Brief
17-4 PH is a martensitic, chromium-nickel-copper precipitation-hardening stainless steel. 17-4 PH stainless steel is capable of attaining a wide range of strength and toughness properties depending on the precipitation or aging temperature used in hardening.  Its valuable combination of  high strength, good corrosion resistance and toughness in both base metals and welds gives designers opportunities to add reliability to their products while simplifying fabrication and often reducing costs. High strength is maintained to approximately 600°F (316℃). This material has good resistance to stress corrosion cracking in the lower strength conditions.

* Chemical composition, %

CSiMnSPNiCrNbCuFe
≤0.07≤1.0≤1.0≤0.03≤0.043.0~5.015.5~17.50.15~0.453.0~5.0Bal

* Typical physical & mechanical property (Annealed)

Density, g/cm3Tensile strength, MPaYield strength, MPaElongation, %Hardness, Rc
7.8011031000535

* Specification

Bar, Rod, WirePlate, Sheet, Strip
ASTM A564, 705, SAE AMS 5644ASTM A693, SAE AMS 5528

* Feature
1. Alloy 17-4PH withstands corrosive attacks better than any of the standard hardenable stainless steels and is comparable to Alloy 304 in most media
2. If there are potential risks of stress corrosion cracking, the higher aging temperatures then must be selected over 1022°F (550℃), preferably 1094°F (590℃). 1022°F (550℃) is the optimum tempering temperature in chloride media
3. 1094°F (590℃) is the optimum tempering temperature in H2S media.
4. The alloy is subject to crevice or pitting attack if exposed to stagnant seawater for any length of time
5. It is corrosion resistant in some chemical, petroleum, paper, dairy and food processing industries (equivalent to 304L grade)

* Application
1. Aerospace – structural and parts
2. Biomedical – hand tools
3. Chemical Processing
4. Food Process Equipment
5. Gate Valves
6. Mechanical Components
7. Nuclear Waste Processing and Storage
8. Oil and Gas Production – foils, helicopter deck platforms, etc.
9. Pulp and Paper – paper mill equipment