Steel H19 QT44-48 vs H19 QT50-52
Steel · H19 temper comparison
H19 QT44-48 and H19 QT50-52 are two conditions of the same steel grade, H19: QT44-48 (hardened & tempered 44–48 HRC) versus QT50-52 (hardened & tempered 50–52 HRC). The chemistry is identical, so every difference below comes from the condition. H19 QT50-52 is the stronger of the two: yield strength 1,520 MPa (220 ksi) against 1,300 MPa (189 ksi) for H19 QT44-48, about 17% more; tensile strength follows at 1,750 MPa (254 ksi) vs 1,500 MPa (218 ksi). In exchange, H19 QT44-48 is the more ductile: elongation 10% versus 8% for H19 QT50-52, and H19 QT50-52 is harder (500 HB vs 435 HB).
H19 QT44-48Choose it when the part is bent, formed or impact-loaded.
H19 QT50-52Choose it when strength drives the design.
H19 QT44-48 vs H19 QT50-52: 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
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 97 HRB
Physical
Density and transition temperatures.
Same in both: Density 8.19 g/cm³0.3 lb/in³ · Melting Point (Solidus) 1,370°C2,498 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.2 µm/m·K6.2 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 2.7 % IACS · Electrical Resistivity 6.5×10⁻⁷ Ω·m25.6 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.55 V · Corrosion Resistance 18 / 100
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: Castability 20 / 100 · Brazeability / Solderability 35 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 45 MJ/kg19,347 BTU/lb · Embodied Carbon (primary production) 3.2 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 40%
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.
H19 QT44-48 vs H19 QT50-52 — frequently asked
Is H19 QT50-52 stronger than H19 QT44-48?
Yes. H19 QT50-52 has a typical yield strength of 1,520 MPa (220 ksi) against 1,300 MPa (189 ksi) for H19 QT44-48 — about 17% more. Tensile strength is 1,750 MPa (254 ksi) vs 1,500 MPa (218 ksi).
Which condition does FabDigit quote by default, QT44-48 or QT50-52?
ANN is the default H19 condition in the FabDigit quote flow (neither QT44-48 nor QT50-52). 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, H19 QT44-48 or H19 QT50-52?
H19 QT44-48. Its machinability rates poor (15/100) against not recommended (10/100) for H19 QT50-52.
Ready to make it?
Upload a CAD file and FabDigit prices the part in H19 QT44-48 and H19 QT50-52 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.