Views:7 Author:Ronsco Publish Time: 2020-05-20 Origin:Stainless Steel Knowledge
What is 17-4PH Stainless Steel?
Alloy 17-4PH is a precipitation hardening martensitic stainless steel with Cu and Nb/Cb additions. The grade combines high strength, hardness (up to 572°F /300°C), and corrosion resistance. Mechanical properties can be optimized with heat treatment. Very high yield strength up to 1100-1300 MPa (160-190 ksi) can be achieved.
Specification Sheet Overview:
for Alloy 17-4PH (UNS S17400)
W. Nr. 1.4542 Type 630:
A Precipitation-Hardening Martensitic Stainless with High Strength and Hardness and Good Corrosion Resistance
Alloy 17-4PH (UNS S17400), Type 630, is a chromium-nickel-copper precipitation-hardening martensitic stainless steel with an addition of niobium. 17-4PH combines high strength and hardness with good corrosion resistance.
The alloy is furnished in the solution annealed condition (Condition A). It should not be used at temperatures above 572°F (300°C) or for cryogenic service. Optimal mechanical properties can be obtained by subjecting the alloy to age hardening heat treatments. Heat treatment in the 900°F (482°C) range produces the highest strength.
The corrosion resistance of Alloy 17-4PH is comparable to 304 stainless steel in most environments, and is generally superior to the 400 series stainless steels. It is used in applications where the combination of moderate corrosion resistance and unusually high strength are required.
Alloy 17-4PH can be easily welded and processed by standard shop fabrication practices. It is magnetic.
Ring rolling is a specialized type of hot rolling that increases the diameter of a ring. The starting material is a thick-walled ring. This workpiece is placed between two rolls, an inner idler roll and a driven roll, which presses the ring from the outside. As the rolling occurs the wall thickness decreases as the diameter increases. The rolls may be shaped to form various cross-sectional shapes. The resulting grain structure is circumferential, which gives better mechanical properties. Diameters can be as large as 8 m (26 ft) and face heights as tall as 2 m (79 in). Common applications include bearings, gears, rockets, turbines, airplanes, pipes, and pressure vessels.
Alloy 17-4PH Processing Videos: