AMS Specification 17-4PH Stainless Steel Stainless Steel

AMS 5643

17-4PH Stainless Steel – Bars, Wire, Forgings, Tubing & Rings

Steel, Bars, Wire, Forgings, Mechanical Tubing, Flash Welded Rings – 16Cr – 4.0Ni – 0.30CbTa – 4.0Cu

AS9100D / ISO 9001

Mill Test Reports

2–4 Week Delivery

877-237-6822

Quick Specification Facts

Spec Number AMS 5643 (AMS5643)

Material 17-4PH Stainless Steel

Spec Type AMS (Aerospace Material Specification)

Category 17-4PH Stainless Steel

Composition 16Cr – 4.0Ni – 0.30CbTa – 4.0Cu

Condition Solution Heat Treated / Precipitation Hardenable

Product Forms Bars, Wire, Forgings, Mechanical Tubing, Flash Welded Rings

Certification AS9100D / ISO 9001 with full MTR traceability

Specification Overview

AMS 5643 (also referenced as AMS5643) is an SAE International aerospace material specification covering 17-4PH stainless steel in the form of bars, wire, forgings, mechanical tubing, flash welded rings, and stock for forging, flash welded rings, or heading. Per SAE International, this specification covers a corrosion-resistant steel in the solution heat treated condition that is precipitation hardenable. The nominal composition of 16% Chromium, 4% Nickel, 4% Copper, and 0.30% Niobium/Tantalum (Columbium/Tantalum) gives this alloy an outstanding combination of high strength, excellent corrosion resistance, and good mechanical properties at both ambient and elevated temperatures.

17-4PH stainless steel is one of the most widely used precipitation-hardening stainless steels in aerospace, defense, and industrial applications. Its chromium content provides excellent corrosion resistance in marine and industrial atmospheres, while the copper addition enables precipitation hardening to achieve high tensile and yield strengths in the aged condition. The material maintains its strength and hardness up to approximately 600°F (316°C) and exhibits excellent dimensional stability during heat treatment. AMS 5643 material is magnetic in all conditions, distinguishing it from austenitic stainless steels.

Available Product Forms

Bars

Wire

Forgings

Mechanical Tubing

Flash Welded Rings

AMS 5643 material is supplied as Bars, Wire, Forgings, Mechanical Tubing, Flash Welded Rings, and stock for forging, flash welded rings, or heading per specification requirements. Standard and custom sizes are available across all product forms. Custom lengths, forging configurations, and pre-machined forms are available upon request. Contact our materials specialists for non-standard dimensions or special requirements.

Nominal Chemical Composition

Element	Symbol	Nominal %	Notes
Chromium	Cr	15.0 – 17.5% (~16%)	Provides corrosion resistance in marine and industrial environments
Nickel	Ni	3.0 – 5.0% (~4%)	Promotes austenite formation; improves toughness and corrosion resistance
Copper	Cu	3.0 – 5.0% (~4%)	Primary precipitation hardening element; enables high strength after aging
Niobium + Tantalum	Nb+Ta	0.15 – 0.45% (~0.30%)	Stabilizes microstructure; prevents sensitization; refines grain size
Carbon	C	0.07% max	Low carbon content minimizes carbide precipitation
Manganese	Mn	1.00% max	Deoxidizer; improves hot workability
Silicon	Si	1.00% max	Deoxidizer; improves oxidation resistance
Iron	Fe	Balance	Base metal

Chemical composition ranges are nominal. Consult the current issue of AMS 5643 for precise minimum/maximum requirements. Aero-Vac provides full mill test reports (MTRs) with certified chemistry for every order.

Key Properties & Specification Details

Property / Attribute	Details
Specification Number	AMS 5643 (AMS5643)
Issuing Organization	SAE International (Society of Automotive Engineers)
Material Type	Precipitation-Hardening Stainless Steel
Steel Grade	17-4PH (UNS S17400)
Nominal Composition	16Cr – 4.0Ni – 0.30CbTa – 4.0Cu
Available Forms	Bars, Wire, Forgings, Mechanical Tubing, Flash Welded Rings
Strength at Elevated Temp.	Maintains strength and hardness up to 600°F (316°C)
Corrosion Resistance	Excellent – suitable for marine and industrial atmospheres
Machinability	Good – best machined in solution-treated (Condition A) state prior to aging
Weldability	Good – weldable; post-weld aging recommended for full strength
Magnetic Properties	Magnetic in all conditions
Dimensional Stability	Excellent – stable during heat treatment cycles
Certification Available	AS9100D / ISO 9001, Certificate of Conformance, MTR

Typical Applications

Aerospace & Defense: Aircraft structural components, fasteners, brackets, shafts, fittings, valve bodies, and high-strength structural assemblies requiring controlled mechanical properties and corrosion resistance.

Chemical & Petrochemical Processing: Valves, pumps, fittings, and process equipment operating in corrosive environments where high strength and corrosion resistance must be maintained simultaneously.

Marine Applications: Marine hardware, fittings, shafts, and structural components requiring resistance to seawater and salt-spray corrosion combined with high tensile strength.

Oil & Gas: Pump shafts, valve components, downhole equipment, and wellhead hardware requiring high strength and corrosion resistance under demanding service conditions.

Medical & Nuclear: Surgical instruments, orthopedic implant components, nuclear waste containment hardware, and precision components requiring dimensional stability and biocompatibility.

Frequently Asked Questions – AMS 5643

What is AMS 5643 and what does it cover?

AMS 5643 (also written AMS5643) is an SAE International aerospace material specification covering 17-4PH stainless steel in the form of bars, wire, forgings, mechanical tubing, flash welded rings, and stock for forging, flash welded rings, or heading. Per SAE International, the specification covers a corrosion-resistant steel in the solution heat treated condition that is precipitation hardenable. The nominal composition of 16% Chromium, 4% Nickel, 4% Copper, and 0.30% Niobium/Tantalum delivers high tensile and yield strength in the aged condition, excellent corrosion resistance in marine and industrial atmospheres, and good mechanical properties up to 600°F (316°C). It is widely used in aerospace, defense, chemical processing, and marine applications.

What heat treatment conditions are available for AMS 5643 17-4PH stainless steel?

17-4PH stainless steel per AMS 5643 is available in several heat treatment conditions that control the final mechanical properties. The most common conditions are: Condition A (solution annealed, highest ductility, lowest strength – best for machining), Condition H900 (aged at 900°F – highest strength), Condition H925, Condition H1025, Condition H1075, Condition H1100, and Condition H1150 (progressively lower strength and higher ductility as aging temperature increases). The H-number refers to the aging temperature in degrees Fahrenheit. Aero-Vac can supply AMS 5643 material in Condition A for customer aging, or in customer-specified aged conditions. Contact us to discuss the condition best suited for your application.

Does Aero-Vac supply AMS 5643 with full mill test reports and certifications?

Yes. All AMS 5643 material supplied by Aero-Vac is fully traceable to mill test reports (MTRs) confirming chemical composition and mechanical properties per the specification. We are AS9100D/ISO 9001 certified with a 99.6% quality rating. Every order ships with certificates of conformance, material certifications, and chemical/mechanical test reports. Electronic delivery of all documentation is available for fast turnaround. If your program requires additional special process certifications, our quality team can coordinate as needed.

What sizes and product forms of AMS 5643 does Aero-Vac stock?

Aero-Vac maintains inventory of AMS 5643 17-4PH stainless steel in multiple product forms including round bar, flat bar, hex bar, wire, and tubing in a range of standard sizes. We carry standard sizes and can provide custom-cut lengths from our in-house processing facility at the Port of Kalama. For forgings and flash welded rings, we work with our qualified forging supplier network to provide certified product to your specific configuration. For non-standard dimensions, our team can source from our global supplier network. Contact us with your specific size and form requirements and we will provide a prompt quote with availability and lead time.

What are the typical lead times for AMS 5643 material?

In-stock AMS 5643 material is typically available for same-day or next-day shipment. For custom-cut or specially processed orders, our standard lead time is 2–4 weeks—significantly faster than the industry average of 8–12 weeks. Specialty items requiring mill production or forging may require 4–8 weeks depending on quantity, form, and dimensions. We prioritize urgent aerospace and defense requirements and will always provide honest, upfront delivery estimates. Rush processing is available on select items.

Can Aero-Vac provide value-added processing for AMS 5643 material?

Yes. Aero-Vac operates a complete in-house processing facility at our Port of Kalama location. For AMS 5643 17-4PH stainless steel, we offer precision saw cutting, surface grinding, turning, milling, and heat treatment services including solution annealing and precipitation hardening aging cycles. We also provide comprehensive mechanical and non-destructive testing services in-house. Having all capabilities under one roof allows for faster turnaround, tighter quality control, and reduced overall cost compared to using multiple vendors. Contact us to discuss your specific processing requirements.

Need AMS 5643 material or a custom quote?

Our stainless steel specialists can provide fast pricing, availability, and technical guidance for your AMS 5643 17-4PH requirements.