Stainless Steel 430 vs S40977
Stainless Steel · grade comparison
Stainless Steel 430 and S40977 are both stainless steel grades. 430 is the stronger of the two: yield strength 310 MPa (45 ksi) against 250 MPa (36.3 ksi) for S40977, about 24% more; tensile strength follows at 500 MPa (72.5 ksi) vs 420 MPa (60.9 ksi). 430 is harder — 155 HB against 145 HB for S40977 — which matters for wear surfaces and threads. 430 runs hotter in service (815°C vs 675°C continuous). On the shop floor, S40977 welds better (excellent vs good), S40977 forms better (very good vs good), and S40977 sits in a lower cost tier (budget, $) than 430 (standard, $$).
430Choose it when strength drives the design, or when surface hardness matters.
S40977Choose it when it will be welded, or when cost is the deciding factor.
430 vs S40977: 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.
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Compressive Strength
Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi · Elongation at Break 30% · Reduction in Area 65% · Fracture Toughness (K_IC) 70 MPa·√m63.7 ksi·√in
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Same in both: Liquidus Temperature 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.9 % IACS · Electrical Resistivity 6×10⁻⁷ Ω·m23.6 µΩ·in
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)
Polishability
Same in both: Brazeability / Solderability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 70%
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 | 430 | S40977 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | Annealed | — |
| Relative cost | $$ Standard | $ Budget |
| Min. machined wall | 0.8 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| AlCrN | Yes | — |
| AlTiN | Yes | — |
| Black Oxide | Yes | — |
| CVD Al2O3 | Yes | — |
| CVD TiCN | Yes | — |
| CVD TiN | Yes | — |
| Cerakote | Yes | — |
| Chrome Plating | Yes | — |
| CrN | Yes | — |
| DLC | Yes | — |
| Electropolishing | Yes | — |
| HVOF Coating | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
| Passivation (Stainless Steel) | Yes | — |
They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.
430 vs S40977 — frequently asked
Is 430 stronger than S40977?
Yes. 430 has a typical yield strength of 310 MPa (45 ksi) against 250 MPa (36.3 ksi) for S40977 — about 24% more. Tensile strength is 500 MPa (72.5 ksi) vs 420 MPa (60.9 ksi).
Which is cheaper, 430 or S40977?
S40977 is the lower-cost material: it sits in the budget tier ($) while 430 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, 430 or S40977?
S40977. Its machinability rates good (55/100) against fair (50/100) for 430; for welding the order is S40977 first (excellent, 85/100) then 430 (good, 60/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 430 and S40977 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.