416 Stainless Steel Shafts

Free-machining martensitic stainless — the easiest stainless to turn, magnetic and hardenable.

At a glance

Stocked condition	Cold finished
Machinability	Very good — the best of our stainless grades
Weldability	Not recommended
Corrosion resistance	Moderate — fresh water and mild atmospheres; avoid chlorides
Hardening	Hardenable by heat treatment (martensitic)
Density (nominal)	0.280 lb/in³
Food contact	No
Magnetic	Yes

416 is a different animal from the 300-series grades: martensitic, so it is magnetic and responds to heat treatment, and sulfurized, so it machines faster than any other stainless we stock. That combination suits valve stems, motor shafts, and pump internals that need rust resistance plus a hardened surface.

Its corrosion resistance is real but the most modest of our stainless grades — fine for fresh water, steam, and mild atmospheres, wrong for chlorides or marine exposure. Welding is not recommended.

Configure a 416 part →

Any geometry in the configurator — diameters, threads, keyseats, grooves, holes, tapers — can be machined in 416. Pick the material in the sidebar and the price updates live.

When to choose 416

You need a stainless that can be hardened after machining.
A magnetic stainless is required (sensors, magnetic couplings).
Lots of machining features in a mildly corrosive environment.

Consider instead

303 — better corrosion resistance when hardening is not needed.
17-4 PH — more strength and better corrosion resistance.
1045 — when plating can cover the corrosion requirement.

Typical applications

Valve stems and trim
Pump shafts (fresh water)
Motor and gear shafts needing rust resistance
Hardened dowels and wear pins

Frequently Asked Questions

Yes — it is martensitic, so unlike the 300-series grades it is strongly magnetic in any condition. That is a feature for sensor and coupling applications.

Yes, by conventional quench-and-temper heat treatment after machining. It is the easy path to a hardened, corrosion-resistant shaft when 17-4's strength is not required.

Good in fresh water, steam, and indoor atmospheres; the weakest of our stainless grades against chlorides and salt. For washdown chemicals or marine air, use 303, 304, or 316.

Stocked as 416 CF — cold finished. Material and condition are paired — each grade ships in one condition optimized for our process; see all grades on the materials page.