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17-4 PH Stainless Steel Forgings

17-4 PH stainless steel is a precipitation-hardening alloy with high strength, outstanding corrosion resistance, and excellent heat treatability. It is commonly used to manufacture components and parts that must perform in demanding sectors, including aerospace, medical, petrochemical, and food-processing applications.

17-4 PH responds exceptionally well to open-die forging. The process refines the alloy's grain structure and closes internal voids, and post-forge heat treatment gives engineers precise control over the final hardness and strength profile. Few materials offer that level of performance in a forged component.

At Great Lakes Forge, we offer a full range of custom forging capabilities for 17-4 PH stainless steel. We can provide custom forgings up to 4,000 lbs., from 3.5" to 18" in diameter/thickness, and up to 120" in length. With the industry's fastest turnaround times, our forging services are ideal for high or low-volume production, as well as prototyping.

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17-4 PH Stainless Steel Alloy: Properties & Characteristics

17-4 PH stainless steel combines high strength, corrosion resistance, and thermal stability in a single alloy. These characteristics translate directly into how parts perform after forging. Components forged from 17-4 PH can withstand high mechanical loads and maintain their properties after heat treatment. Characteristics of 17-4 PH stainless steel include:

  • High strength
  • High hardness
  • High fatigue strength
  • Good galling and stress corrosion resistance
  • Exceptional oxidation resistance at temperatures up to 1,100°F (593°C)
  • Excellent corrosion resistance (comparable to chromium-nickel grades)

Forged 17-4 Stainless Steel Composition and Mechanical Properties

Element % Content
Carbon 0.07 (max.)
Chromium 14.00 to 15.50
Columbium + Tantalum 0.15 to 0.45
Copper 2.50 to 4.50
Manganese 1.00 (max.)
Nickel 3.50 to 5.50
Phosphorous 0.040 (max.)
Silicon 1.00 (max.)
Sulfur 0.015 (max.)
Iron balance

17-4 PH stainless steel offers a combination of high-performance mechanical properties that make it ideal for open-die forging. After forging, these characteristics translate into reliable components for aerospace, medical, petrochemical, and food processing applications. Mechanical properties of 17-4PH forgings include:

  • Hardness: Tempered 17-4 stainless steel can reach Brinell scale hardness of up to 388 and Rockwell hardness of up to C40. This high hardness provides wear resistance for components subject to friction and abrasive contact.
  • Heat Treatment: 17-4 PH is hardened by heating solution-treated material to temperatures from 900°F to 1,150°F (482°C to 621°C) for one to four hours, then air-cooled to below 90°F (32°C) to allow for complete martensite transformation.
  • Machinability: 17-4 PH is readily machined in both solution-treated (condition A) and precipitation-hardened conditions. Surface cutting speed for annealed 17-4 averages 80 ft/min, similar to 13-8 stainless steel.
  • Weldability: 17-4 PH can be welded using standard methods, though post-weld heat treatment is generally recommended to restore mechanical properties in the heat-affected zone.
  • Hot and Cold Working: 17-4 PH can be hot-worked within a specific temperature range to achieve complex geometries while retaining strength and toughness. Cold working is possible but limited by the alloy's high initial yield strength.

Forged 17-4 Stainless Steel Applications and Industries

17-4 PH stainless steel is one of the more versatile materials in Great Lakes Forge's inventory. Its combination of high strength, corrosion resistance, and post-forge heat treatability is essential for many critical components across several demanding industries. 17-4 stainless steel forgings serve a variety of industries where performance and reliability are non-negotiable.

Common applications for forged 17-4 PH stainless steel include:

  • Aerospace: Aircraft structural components, engine parts, and landing gear assemblies that require high strength-to-weight ratio and fatigue resistance.
  • Oil & Gas: Drilling equipment, valve bodies, and downhole tools that must hold up under high pressure and corrosive environments.
  • Power Generation: Turbine components, pump shafts, and machinery parts that see sustained mechanical load and elevated temperatures.
  • Marine and Shipbuilding: Structural and mechanical components that require reliable corrosion resistance in high-chloride, saltwater environments.
  • Chemical and Petrochemical: High-stress structural parts and process components exposed to aggressive chemicals and elevated pressures.
  • Food Processing: Durable gears, shafts, and cutting components that require corrosion resistance and sanitary material properties.

Available Shapes for Forged 17-4 PH Stainless Steel

Great Lakes Forge produces 17-4 PH stainless steel forgings in a wide range of standard and custom shapes to meet your project specifications. Available shapes include:


Secondary Services and Heat Treatment for 17-4 PH Forgings

Great Lakes Forge also offers in-house secondary services, including CNC milling, rough turning, and quality-controlled testing, to bring forged 17-4 PH components closer to finished specifications without adding additional vendors.

Because 17-4 PH is a precipitation-hardening alloy, heat treating after forging is often a critical part of the process. Our heat treatment capabilities allow us to target specific hardness and strength profiles for each component, making your finished part meet the mechanical requirements of its intended application.

Why Choose GL Forge for Open-Die Forged 17-4 Stainless Steel?

With over 60 years of open-die forging experience, Great Lakes Forge has the equipment and expertise to produce premium custom forgings from demanding materials like 17-4 PH stainless steel. Forging, machining, and heat treatment are all done in-house, which means fewer handoffs and shorter lead times.

What sets Great Lakes Forge apart:

  • Experience: 60+ years producing open-die forgings for critical industrial applications
  • In-House Capabilities: Forging, CNC machining, heat treating, and quality-controlled testing under one roof in the USA
  • Fast Turnaround: Some of the fastest lead times in the industry, from prototypes to production runs, with quick delivery
  • Quality Assurance: Rigorous quality processes built to meet aerospace, oil and gas, and food processing standards

Your Trusted 17-4 Stainless Steel Forging Expert

Start your 17-4 Steel forging project today with Great Lakes Forge. We have the ability and capacity to exceed your stainless steel forging needs.

Request a quote on the custom 17-4 stainless steel forgings you need. Or, contact Great Lakes Forge for more information.