Steel Q550 vs S700MC
Steel · grade comparison
Steel Q550 and S700MC are both steel grades. S700MC is the stronger of the two: yield strength 740 MPa (107 ksi) against 590 MPa (85.6 ksi) for Q550, about 25% more; tensile strength follows at 810 MPa (117 ksi) vs 730 MPa (106 ksi). In exchange, Q550 is the more ductile: elongation 18% versus 14% for S700MC, and S700MC is harder (245 HB vs 225 HB). Q550 runs hotter in service (350°C vs 300°C continuous). On the shop floor, S700MC welds better (excellent vs very good) and Q550 sits in a lower cost tier (budget, $) than S700MC (standard, $$).
Q550Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
S700MCChoose it when strength drives the design, or when it will be welded.
Q550 vs S700MC: 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.
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Reduction in Area 55%
Physical
Density and transition temperatures.
Melting Point (Solidus)
Liquidus Temperature
Same in both: Density 7.85 g/cm³0.28 lb/in³
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V · Corrosion Resistance 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Weldability
Formability (cold)
Polishability
Brazeability / Solderability
Same in both: Machinability 45 / 100 · Machinability Rating (AISI 1212 = 100 %) 50%
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Embodied Water
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Typical Recycled Content 25%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg
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 | Q550 | S700MC |
|---|---|---|
| Sheet metal | — | Yes |
| Default condition | — | TMCP |
| Relative cost | $ Budget | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
| Black Oxide | — | Yes |
| Cerakote | — | Yes |
| Chrome Plating | — | Yes |
| E-Coating | — | Yes |
| Hot-Dip Galvanizing | — | Yes |
| Nickel Plating | — | Yes |
| PTFE Coating | — | Yes |
| Painting | — | Yes |
| Powder Coating | — | Yes |
| Tin Plating | — | Yes |
| Zinc Plating | — | Yes |
| Zinc-Flake (Dip-Spin) Coating | — | Yes |
| Zinc-Nickel Plating | — | 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.
Q550 vs S700MC — frequently asked
Is S700MC stronger than Q550?
Yes. S700MC has a typical yield strength of 740 MPa (107 ksi) against 590 MPa (85.6 ksi) for Q550 — about 25% more. Tensile strength is 810 MPa (117 ksi) vs 730 MPa (106 ksi).
Which is cheaper, Q550 or S700MC?
Q550 is the lower-cost material: it sits in the budget tier ($) while S700MC 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, Q550 or S700MC?
S700MC. Its weldability rates excellent (85/100) against very good (72/100) for Q550.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Q550 and S700MC 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.