Material specification

AMS 5643

SAE's material specification for corrosion-resistant steel bars, wire, forgings, mechanical tubing and rings in the 16Cr-4.0Ni-0.30Cb-4.0Cu alloy, solution heat treated and precipitation hardenable. DLA catalog records pair it with 17-4 PH.

8,473 NSNs in DLA's catalog cite this spec. See the catalog data

What AMS 5643 covers

AMS 5643 is titled "Steel, Corrosion-Resistant, Bars, Wire, Forgings, Mechanical Tubing, and Rings, 16Cr - 4.0Ni - 0.30Cb (Nb) - 4.0Cu, Solution Heat Treated, Precipitation Hardenable".

It covers bars, wire, forgings, mechanical tubing and flash welded rings in the solution heat treated condition, up to 8.0 inches (203 mm). DLA catalog callouts that add a grade name it as 17-4 PH and composition 630.

Product forms and condition

Product forms
Bars, wire, forgings, mechanical tubing and flash welded rings.
Size
Up to 8.0 inches (203 mm), per the current revision's scope.
Delivered condition
Solution heat treated. The alloy is precipitation hardenable, so the final heat treat condition comes from the drawing.
Conditions named in DLA callouts
Catalog records that add a condition to AMS 5643 most often name Condition A and Condition H1025.

Status and revisions

AMS 5643 was first issued in October 1951. The current revision is AMS 5643W, revised 13 December 2021.

Typical applications

  • Sleeve bushings, quick-release pins, sleeve bearings and straight pins lead DLA's catalog, followed by self-aligning and rod end plain bearings and machine bolts.
  • Passivation is the finish most often called out with it in the catalog, followed by cadmium and chromium on some parts.

What a shop needs to supply to AMS 5643

  • Buy bar or forgings certified to AMS 5643 at the revision the order names, and keep the material certification with the job.
  • Confirm the heat treat condition the drawing requires. The material ships solution heat treated; any precipitation hardening condition comes from the drawing.
  • Check the finish callout. Most catalog records for AMS 5643 parts also call for passivation.

The purchase order, drawing and the revision of the spec it invokes govern. Always work from the revision your contract names.

AMS 5643 in the DLA catalog

From DLA's public PUB LOG catalog, release 2026-10-27, covering 16 hardware and mechanical supply groups (fasteners, bearings, fittings, valves, power transmission, engine components and more).

8,473
NSNs whose catalog record cites AMS 5643
46%
coded open to new sources (3,903 NSNs): at least one managing service codes it AMC 1 or 2 with AMSC G
37%
coded for existing or approved sources (3,162 NSNs)

Most common items

Bushing, sleeve2,125
Pin, quick release2,102
Bearing, sleeve635
Pin, straight, headless190
Bearing, plain, self-aligning182
Pin, shoulder, headless174
Bearing, plain, rod end152
Bolt, machine149
Collar, pin-rivet113
Spacer, sleeve112

Federal supply classes

3120 Bearings, plain, unmounted3,044
5315 Nails, machine keys, and pins2,775
5310 Nuts and washers416
5340 Hardware, commercial345
5365 Bushings, rings, shims, and spacers340
5306 Bolts330
5305 Screws211
5320 Rivets135

Can a new source win these parts?

DLA codes each part with an acquisition method (AMC) and a suffix (AMSC). We count an NSN as open when at least one managing service codes it AMC 1 or 2 (competitive) with suffix G (the government has the full technical data and the rights to use it). Otherwise we count it as restricted when a service codes it AMC 3, 4 or 5 (buy from the manufacturer or prime) or uses a suffix that limits or conditions who can supply it (AMSC B, C, D, H, K, L, P, Q, R, T, U or Y): missing data or rights, source-control drawings, source or QPL approval, controlled castings, uneconomical breakout, an unstable design, or low-value screening for known sources. These are catalog codes; the solicitation always governs.

Open: AMC 1 or 2 with AMSC G3,90346%
Restricted: AMC 3, 4 or 5, or a restrictive AMSC3,16237%
Other acquisition codes7419%
No acquisition method in the catalog6678%

As of PUB LOG release 2026-10-27. How to read the codes: AMC and AMSC codes explained.

How catalog records call it out

Characteristic records that cite AMS 5643, grouped by the type, class or condition they name. Counted across the most common callout spellings, so the totals are a floor.

Not specified10,081
Condition A86
Condition H102573

Finishes called out on these parts

  • Passivate (overall) 2,284
  • Passivate (spindle) 1,185
  • Passivate (shank) 628
  • Passivate 205
  • Cadmium (overall) 181
  • Cadmium and chromate (overall) 154
  • Chromium (overall) 71
  • Diameter surface of body chromium (outside) 44

Sample NSNs that cite AMS 5643

Stainless steel machine shops in the directory

67 listed shops report this capability. Confirm the spec, revision and any approvals with the shop before you order.

See all stainless steel machine shops

Frequently asked questions

What is AMS 5643?

An SAE specification for corrosion-resistant steel bars, wire, forgings, mechanical tubing and rings in the 16Cr-4.0Ni-0.30Cb-4.0Cu alloy, solution heat treated and precipitation hardenable. DLA catalog records pair it with 17-4 PH.

What is the current revision of AMS 5643?

AMS 5643W, revised 13 December 2021. The spec was first issued in October 1951.

What size range does AMS 5643 cover?

The current revision covers product in the solution heat treated condition up to 8.0 inches (203 mm).

How many DLA parts cite AMS 5643?

8,473 NSNs in DLA's PUB LOG catalog (release 2026-10-27, 16 hardware and mechanical supply groups), led by sleeve bushings and quick-release pins.

Related

Sources