Titanium ZTC4 Annealed vs ZTC4-STA
Titanium · ZTC4 temper comparison
ZTC4 Annealed and ZTC4-STA are two conditions of the same titanium grade, ZTC4: Annealed versus STA (solution treated and aged). The chemistry is identical, so every difference below comes from the condition. ZTC4-STA is the stronger of the two: yield strength 930 MPa (135 ksi) against 840 MPa (122 ksi) for ZTC4 Annealed, about 11% more; tensile strength follows at 1,020 MPa (148 ksi) vs 910 MPa (132 ksi). In exchange, ZTC4 Annealed is the more ductile: elongation 8% versus 6% for ZTC4-STA, and ZTC4-STA is harder (350 HB vs 325 HB). ZTC4 Annealed runs hotter in service (350°C vs 315°C continuous).
ZTC4 AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
ZTC4-STAChoose it when strength drives the design.
ZTC4 Annealed vs ZTC4-STA: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all titanium 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 titanium 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
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 110 GPa16 Msi · Shear Modulus 42 GPa6.1 Msi · Bulk Modulus 110 GPa16 Msi · Poisson's Ratio 0.34 · Compressive Strength 970 MPa141 ksi · Shear Strength 580 MPa84.1 ksi
Physical
Density and transition temperatures.
Same in both: Density 4.43 g/cm³0.16 lb/in³ · Melting Point (Solidus) 1,604°C2,919 °F · Liquidus Temperature 1,660°C3,020 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 7 W/m·K4 BTU/hr·ft·°F · Specific Heat Capacity 560 J/kg·K0.13 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 8.8 µm/m·K4.9 µin/in·°F · Latent Heat of Fusion 365 J/g157 BTU/lb · Min Service Temperature -253°C-423 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 1 % IACS · Electrical Resistivity 1.71×10⁻⁶ Ω·m67.3 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.12 V · Corrosion Resistance 88 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Same in both: Machinability Rating (AISI 1212 = 100 %) 20% · Weldability 75 / 100 · Formability (cold) 10 / 100 · Castability 68 / 100 · Brazeability / Solderability 40 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 700 MJ/kg300,946 BTU/lb · Embodied Carbon (primary production) 45 kg CO₂/kg · Embodied Water 600 L/kg71.9 gal/lb · Typical Recycled Content 25%
Strength versus weight
Yield strength against density for every titanium grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
ZTC4 Annealed vs ZTC4-STA — frequently asked
Is ZTC4-STA stronger than ZTC4 Annealed?
Yes. ZTC4-STA has a typical yield strength of 930 MPa (135 ksi) against 840 MPa (122 ksi) for ZTC4 Annealed — about 11% more. Tensile strength is 1,020 MPa (148 ksi) vs 910 MPa (132 ksi).
Which condition does FabDigit quote by default, Annealed or STA?
Annealed is the default ZTC4 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.
When should I choose ZTC4 Annealed over ZTC4-STA?
Pick ZTC4 Annealed when the part is bent, formed or impact-loaded, or when the part sees heat. Pick ZTC4-STA when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in ZTC4 Annealed and ZTC4-STA 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.