Steel 4620 vs 4720
Steel · grade comparison
Steel 4620 and 4720 are both steel grades. 4720 is the stronger of the two: yield strength 430 MPa (62.4 ksi) against 360 MPa (52.2 ksi) for 4620, about 19% more; tensile strength follows at 640 MPa (92.8 ksi) vs 570 MPa (82.7 ksi). In exchange, 4620 is the more ductile: elongation 26% versus 23% for 4720, and 4720 is harder (200 HB vs 163 HB). 4620 runs hotter in service (400°C vs 350°C continuous). On the shop floor, 4620 welds better (65 vs 55 out of 100) and 4720 sits in a lower cost tier (budget, $) than 4620 (standard, $$).
4620Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
4720Choose it when strength drives the design, or when cost is the deciding factor.
4620 vs 4720: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all 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 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Compressive Strength
Fracture Toughness (K_IC)
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 55%
Physical
Density and transition temperatures.
Melting Point (Solidus)
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Liquidus Temperature 1,500°C2,732 °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)
Same in both: Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Same in both: Machinability Rating (AISI 1212 = 100 %) 65%
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Same in both: Embodied Carbon (primary production) 2.2 kg CO₂/kg · Typical Recycled Content 30%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Specific Stiffness (E / density) 26.1 MN·m/kg · Thermal Shock Resistance Index 11
Strength versus weight
Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 4620 | 4720 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | HR | — |
| 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 | — |
| E-Coating | Yes | — |
| HVOF Coating | Yes | — |
| Hot-Dip Galvanizing | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
4620 vs 4720 — frequently asked
Is 4720 stronger than 4620?
Yes. 4720 has a typical yield strength of 430 MPa (62.4 ksi) against 360 MPa (52.2 ksi) for 4620 — about 19% more. Tensile strength is 640 MPa (92.8 ksi) vs 570 MPa (82.7 ksi).
Which is cheaper, 4620 or 4720?
4720 is the lower-cost material: it sits in the budget tier ($) while 4620 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 welds better, 4620 or 4720?
4620. Its weldability rates good (65/100) against good (55/100) for 4720.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 4620 and 4720 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.