Steel 34CrAlMo5-10 vs SACM645
Steel · grade comparison
Steel 34CrAlMo5-10 and SACM645 are both steel grades. SACM645 is the stronger of the two: yield strength 780 MPa (113 ksi) against 720 MPa (104 ksi) for 34CrAlMo5-10, about 8% more; tensile strength follows at 950 MPa (138 ksi) vs 900 MPa (131 ksi). SACM645 is the more ductile: elongation 17% versus 14% for 34CrAlMo5-10. 34CrAlMo5-10 runs hotter in service (500°C vs 450°C continuous).
34CrAlMo5-10Choose it when the part sees heat.
SACM645Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.
34CrAlMo5-10 vs SACM645: 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.
Elastic (Young's) Modulus
Shear Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Fatigue Strength (Endurance Limit) 430 MPa62.4 ksi
Physical
Density and transition temperatures.
Melting Point (Solidus)
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Liquidus Temperature 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Same in both: Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Polishability
Brazeability / Solderability
Same in both: Formability (cold) 25 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Water 55 L/kg6.6 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 steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 34CrAlMo5-10 | SACM645 |
|---|---|---|
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| Default condition | — | Q&T |
| Relative cost | $$ Standard | $$ Standard |
| 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.
34CrAlMo5-10 vs SACM645 — frequently asked
Is SACM645 stronger than 34CrAlMo5-10?
Yes. SACM645 has a typical yield strength of 780 MPa (113 ksi) against 720 MPa (104 ksi) for 34CrAlMo5-10 — about 8% more. Tensile strength is 950 MPa (138 ksi) vs 900 MPa (131 ksi).
Which is cheaper, 34CrAlMo5-10 or SACM645?
Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose 34CrAlMo5-10 over SACM645?
Pick 34CrAlMo5-10 when the part sees heat. Pick SACM645 when strength drives the design, or when the part is bent, formed or impact-loaded.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 34CrAlMo5-10 and SACM645 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.