Steel X65-N vs X65-Q
Steel · X65 temper comparison
X65-N and X65-Q are two conditions of the same steel grade, X65: N (normalized) versus Q (quenched and tempered, PSL2). The chemistry is identical, so every difference below comes from the condition. X65-Q is the stronger of the two: yield strength 515 MPa (74.7 ksi) against 485 MPa (70.3 ksi) for X65-N, about 6% more. X65-Q is harder — 195 HB against 185 HB for X65-N — which matters for wear surfaces and threads.
X65-QChoose it when strength drives the design, or when surface hardness matters.
X65-N vs X65-Q: 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
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 68% · Compressive Strength 495 MPa71.8 ksi · Shear Strength 350 MPa50.8 ksi · Fracture Toughness (K_IC) 200 MPa·√m182 ksi·√in · Hardness, Rockwell B 89 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,505°C2,741 °F
Thermal
How each material carries heat and how hot it can run.
Min Service Temperature
Same in both: Thermal Conductivity 47 W/m·K27.2 BTU/hr·ft·°F · 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 · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 250°C482 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 8.6 % IACS · Electrical Resistivity 2×10⁻⁷ Ω·m7.87 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.68 V · Corrosion Resistance 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Same in both: Machinability Rating (AISI 1212 = 100 %) 60% · Brazeability / Solderability 45 / 100 · Polishability 40 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 20%
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.
X65-N vs X65-Q — frequently asked
Is X65-Q stronger than X65-N?
Yes. X65-Q has a typical yield strength of 515 MPa (74.7 ksi) against 485 MPa (70.3 ksi) for X65-N — about 6% more. Tensile strength is 615 MPa (89.2 ksi) vs 590 MPa (85.6 ksi).
Which condition does FabDigit quote by default, N or Q?
M is the default X65 condition in the FabDigit quote flow (neither N nor Q). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which is easier to machine, X65-N or X65-Q?
X65-N. Its machinability rates good (57/100) against fair (50/100) for X65-Q.
Ready to make it?
Upload a CAD file and FabDigit prices the part in X65-N and X65-Q 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.