17/4PH Fasteners

Grade 17-4 PH (1.4542) is one of the most common precipitation hardening stainless grades used for the manufacture of our Special Fasteners and our Non-Standard Socket Screws. 17-4 PH has good corrosion resistance whilst also offering high strength and good impact toughness, vital properties in many special bolting applications. 17/4PH is often specified where the following characteristics are required: • Good corrosion resistance (slightly less than a 304 stainless steel) • High hardness and high strength • Controlled balance of mechanical properties by ageing (precipitation hardening) • Improved toughness compared to 431 stainless and critically at sub-zero temperatures in the softer conditions • Magnetic • Thermal expansion comparable to carbon steel • Easier to weld than martensitic stainless grades like 420 and 431 17-4 PH develops its high strength from the precipitation of copper particles in its martensitic matrix. It comes in various conditions denoted by H plus the ageing temperature in Fahrenheit (°F), for example H900, H1025 etc. The higher the ageing temperature, the lower the strength becomes and the higher the ductility and toughness develop. The minimum 0.2% Proof Stress values can vary from 520 MPa to 1170 MPa depending on the condition. CONDITION A Soak at 1900 F (1038 C) for 30 minutes and cool below 60 F (16 C) for complete martensite transformation. CONDITION H950 Treat Condition A material at 900 F(482 C) for 1 hour, air cool. CONDITION H925, H1025, H1075, H1100, H1150 Soak solution treated material for 4 hours at specified temperature, air cool. CONDITION H1150M Soak solution treated material at 1400 F (760 C) for 2 hours, air cool, then re-heat to 1150 F (620 C) for 4 hours and air cool. The combination of high strength and good corrosion resistance finds special fasteners used in: Drive shafts, gears, hydraulic rams, valve stems, load cells, tensioning systems, quick release pins, fasteners, aerospace, medical devices, food processing, conveying equipment and fall arrest systems Alternative Designations AISI 630 AMS 5604 AMS 5622 AMS 5643 ASTM A564 (630) ASTM A693 (630) ASTM A705 (630) MIL C-24111 MIL P-47183 MIL S-81591 UNS S17400 Carpenter Custom 630 17-4 AL 17-4 Marinox 1 CSM 21 MAXX 17-4 17/4PH 17-4 PH is the quality choice of high strength, corrosion resistant steel fasteners.

For more information on 17/4PH Fasteners talk to Hague Special Fasteners Limited