17-4PH(UNS S17400) AMS 5604 Tube /  Pipe 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°C). This material has good resistance to stress corrosion cracking in the lower strength conditions.