Stainless Steel 17-4 PH vs 316
Stainless Steel · grade comparison
Stainless Steel 17-4 PH and 316 are both stainless steel grades. 17-4 PH is the stronger of the two: yield strength 760 MPa (110 ksi) against 290 MPa (42.1 ksi) for 316, about 162% more; tensile strength follows at 1,030 MPa (149 ksi) vs 580 MPa (84.1 ksi). In exchange, 316 is the more ductile: elongation 50% versus 12% for 17-4 PH, and 17-4 PH is harder (311 HB vs 150 HB). 316 runs hotter in service (870°C vs 200°C continuous). On the shop floor, 17-4 PH machines more easily (45 vs 35 out of 100) and 316 welds better (excellent vs very good).
17-4 PHChoose it when strength drives the design, or when the part is machined in volume.
316Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
Buyer's decision notes
Choose 17-4 PH when a machined stainless part needs strength and hardness established by a controlled aging condition. Choose 316 when corrosion margin, formability and austenitic fabrication behavior lead, and the design does not need precipitation-hardened strength.
Compare the same condition
The base-grade routes hide the most important variable: 17-4 properties depend on solution treatment and the named aging condition, while 316 may be annealed or cold worked. Select the exact product form and condition for each side before comparing values.
- 17-4 condition
- Do not release “17-4 PH” without the final condition. H900, H1025, H1150 and other aging routes trade strength, toughness and corrosion behavior; Carpenter warns that solution-treated Condition A should receive age hardening before service.
- Machining sequence
- 17-4 is often rough- or finish-machined in Condition A and then aged, but the final thermal cycle can move dimensions. Set machining allowance, age condition, straightening permission and final inspection sequence on the purchase order.
- Corrosion exposure
- 316 offers a different corrosion profile, but neither grade carries a blanket saltwater guarantee. Review chloride concentration, temperature, crevices, stress, surface condition and galvanic contacts against the exact 17-4 age condition or 316 product.
- Welded assembly
- A welded 17-4 component needs a procedure coordinated with solution treatment and aging. A welded 316 design needs filler, heat-tint removal and sensitization controls; grade selection alone does not define the finished joint.
Put this on the RFQ
- For 17-4, state UNS grade, product specification, solution-treated delivery state, final H condition, heat-treatment responsibility and final test requirements.
- For 316, state 316 or 316L, annealed or cold-worked condition, product form, applicable specification and certification.
- For either, identify corrosion exposure, welds, critical dimensions after heat treatment, surface finish and passivation requirements.
Primary references
- Carpenter Technology — Custom 630 (17-4 PH) — Producer datasheet distinguishing Condition A and multiple age-hardened conditions, fabrication and corrosion considerations.
- ASTM — A564/A564M — Active specification for hot-rolled and cold-finished age-hardening stainless steel bars and shapes.
FabDigit resources: 17-4 PH datasheet, 316 datasheet, CNC design guide and sheet-metal design guide.
17-4 PH vs 316: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Hardness, Rockwell B
Same in both: Shear Modulus 77 GPa11.2 Msi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Thermal Conductivity 16.3 W/m·K9.4 BTU/hr·ft·°F · Latent Heat of Fusion 270 J/g116 BTU/lb
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Water 200 L/kg24 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 17-4 PH | 316 |
|---|---|---|
| 3D printing | Yes | — |
| Default condition | Condition A | Solution Annealed |
| Relative cost | $$$ Premium | $$$ Premium |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 1.6 µm |
| Electropolished (Metal AM) | Yes | — |
| Passivated (Metal AM) | Yes | — |
| Plated (Metal AM) | Yes | — |
Both are offered for CNC machining, Sheet metal and Casting & forging. They share 32 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, CrN, DLC, Electroless Nickel (EN), Electropolishing and 20 more.
17-4 PH vs 316 — frequently asked
Is 17-4 PH stronger than 316?
Yes. 17-4 PH has a typical yield strength of 760 MPa (110 ksi) against 290 MPa (42.1 ksi) for 316 — about 162% more. Tensile strength is 1,030 MPa (149 ksi) vs 580 MPa (84.1 ksi).
Which is cheaper, 17-4 PH or 316?
Both sit in the same relative cost tier ($$$, premium); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, 17-4 PH or 316?
17-4 PH, by a small margin. Both rate fair for machinability — 45/100 against 35/100 for 316; for welding the order is 316 first (excellent, 88/100) then 17-4 PH (very good, 70/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 17-4 PH and 316 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.