Tungsten Alloy Class 3 Tungsten SINT vs Class 3 Tungsten-SR
Tungsten Alloy · Class 3 Tungsten temper comparison
Class 3 Tungsten SINT and Class 3 Tungsten-SR are two conditions of the same tungsten alloy grade, Class 3 Tungsten: SINT (sintered) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. Class 3 Tungsten-SR is the stronger of the two: yield strength 900 MPa (131 ksi) against 250 MPa (36.3 ksi) for Class 3 Tungsten SINT, about 3.6 times as much; tensile strength follows at 1,100 MPa (160 ksi) vs 300 MPa (43.5 ksi). Class 3 Tungsten-SR is the more ductile: elongation 2% versus 0% for Class 3 Tungsten SINT, and Class 3 Tungsten-SR is harder (46 HRC vs 30 HRC). Class 3 Tungsten SINT is lighter (18.2 g/cm³ vs 19 g/cm³ for Class 3 Tungsten-SR) and Class 3 Tungsten-SR is stiffer (400 GPa vs 345 GPa).
Class 3 Tungsten SINTChoose it when weight is the constraint.
Class 3 Tungsten-SRChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
Class 3 Tungsten SINT vs Class 3 Tungsten-SR: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all tungsten alloy 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 tungsten alloy 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.
Class 3 Tungsten SINTClass 3 Tungsten-SR
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Rockwell C
Hardness, Vickers
Same in both: Shear Modulus 156 GPa22.6 Msi · Bulk Modulus 310 GPa45 Msi · Poisson's Ratio 0.28
Physical
Density and transition temperatures.
Density
Same in both: Melting Point (Solidus) 3,410°C6,170 °F · Liquidus Temperature 3,422°C6,192 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Same in both: Specific Heat Capacity 134 J/kg·K0.03 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 4.5 µm/m·K2.5 µin/in·°F · Latent Heat of Fusion 192 J/g82.5 BTU/lb · Max Service Temperature (continuous) 500°C932 °F · Min Service Temperature 20°C68 °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) -0.15 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Brazeability / Solderability 45 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 400 MJ/kg171,969 BTU/lb · Embodied Carbon (primary production) 28 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb · Typical Recycled Content 25%
Strength versus weight
Yield strength against density for every tungsten alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Class 3 Tungsten SINT vs Class 3 Tungsten-SR — frequently asked
Is Class 3 Tungsten-SR stronger than Class 3 Tungsten SINT?
Yes. Class 3 Tungsten-SR has a typical yield strength of 900 MPa (131 ksi) against 250 MPa (36.3 ksi) for Class 3 Tungsten SINT — about 3.6 times as much. Tensile strength is 1,100 MPa (160 ksi) vs 300 MPa (43.5 ksi).
Which condition does FabDigit quote by default, SINT or SR?
SR is the default Class 3 Tungsten condition in the FabDigit quote flow. 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, Class 3 Tungsten SINT or Class 3 Tungsten-SR?
Class 3 Tungsten SINT. Its machinability rates poor (15/100) against not recommended (10/100) for Class 3 Tungsten-SR.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Class 3 Tungsten SINT and Class 3 Tungsten-SR 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.