Titanium SP-700-ST (Solution annealed)
Heat-treated state
Metastable-β rich, softest and most formable state; form or head parts here then age to final strength.
Values for the ST condition
Other SP-700 tempers and conditions
SP-700 is listed in 6 conditions; see the grade overview at SP-700.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
STThis page Solution annealed | Metastable-β rich, softest and most formable state; form or head parts here then age to final strength. | 790 | 900 | 20 | 30 HRC | 1 % IACS |
AnnealedDefault mill annealed sheet/plate/bar (fine-grained) | Standard stocked condition; fine equiaxed grain for superplastic forming and best cold formability. | 860 | 930 | 17 | 32 HRC | — |
As-welded (GTAW/EBW joint, inert shielding, no PWHT) | Reference condition for weld joints; strength near annealed base metal but reduced ductility — stress relief recommended. | 870 | 930 | 8 | 34 HRC | 1 % IACS |
annealed above β transus (≈900 °C) and cooled | Use when damage tolerance / fracture toughness matters more than ductility (thick plate, forgings). | 880 | 960 | 10 | 33 HRC | 7 W/m·K |
Cold rolled | Cold-worked strip and wire where springback and higher as-supplied strength are wanted; limited remaining ductility. | 1,010 | 1,080 | 8 | 36 HRC | 1 % IACS |
Solution treated and aged | Choose for maximum strength in fasteners, springs and thick sections — SP-700 hardens through much heavier sections than Ti-6Al-4V. | 1,150 | 1,250 | 10 | 39 HRC | — |
What is SP-700-ST?
SP-700-ST is SP-700 heat treated to ST — metastable-β rich, softest and most formable state; form or head parts here then age to final strength. SP-700-ST has a yield strength of 790 MPa (115 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 55% of titanium grades. Elongation at break is 20% and the elastic modulus is 110 GPa (16 Msi). SP-700-ST has a density of 4.54 g/cm³ (0.164 lb/in³), heavier than 80% of titanium grades. It melts at 1,590°C (2,894 °F). Annealed is the default condition FabDigit quotes; ST is available on request or by drawing note.
Limitations
- Low electrical conductivity — 1 % IACS, worse than 89% of titanium grades
SP-700-ST properties
Typical room-temperature values for SP-700-ST; 22 are specific to this condition. Other listed values are SP-700 reference data and may not represent this condition. Bars are the position among titanium grades.
Physical3
SP-700-ST has a density of 4.54 g/cm³ (0.164 lb/in³), heavier than 80% of titanium grades. It melts at 1,590°C (2,894 °F).
Mechanical16
SP-700-ST has a yield strength of 790 MPa (115 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 55% of titanium grades. Elongation at break is 20% and the elastic modulus is 110 GPa (16 Msi).
Thermal6
SP-700-ST is rated for continuous service to 300°C (572 °F). It conducts heat at 7 W/m·K (4.04 BTU/hr·ft·°F), worse than 76% of titanium grades. Thermal expansion is 9.4 µm/m·K (5.22 µin/in·°F).
Electrical3
SP-700-ST conducts electricity at 1 % IACS, worse than 89% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), worse than 77% of titanium grades.
Sustainability4
Producing a kilogram of SP-700-ST takes about 650 MJ of energy and emits 42 kg of CO₂ — less than 75% of titanium grades. Typical recycled content is 25%.
Manufacturability8
SP-700-ST's machinability is poor (22/100, worse than 55% of titanium grades); weldability very good (70/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SP-700-ST
Is SP-700 easy to machine?
Machine like Ti-6Al-4V but harder in STA: low surface speed (20–35 m/min carbide), heavy positive rake, rigid setup, flood high-pressure coolant, never dwell — chips are pyrophoric.
Can SP-700 be welded?
GTAW, plasma, laser and electron-beam weld well with full argon/vacuum shielding and clean joints; diffusion bonding is a designed-in capability, no filler needed for SPF/DB panels.
Can SP-700 be formed, bent or molded?
Superplastic at 750–800 °C with m ≈ 0.5 and >500 % elongation (about 100 °C below Ti-6Al-4V); cold bending is possible at larger radii than Ti-6Al-4V, hot form/size otherwise, then age.
What surface finishes work on SP-700?
Pickle in HNO₃/HF to remove alpha case after hot work, then bead blast, polish or Type II colour anodize; avoid chlorinated cleaners and cadmium/mercury contact.
SP-700 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Alα stabilizer | 4 – 5 | 4.5 |
| Vβ stabilizer | 2.5 – 3.5 | 3 |
| Moβ stabilizer | 1.7 – 2.3 | 2 |
| Festrong β stabilizer, lowers β transus | 1.7 – 2.3 | 2 |
| Ointerstitial, controlled low for superplasticity | ≤ 0.15 | 0.1 |
| C | ≤ 0.05 | — |
| N | ≤ 0.03 | — |
| H | ≤ 0.02 | — |
| Tibalance, ≈88.5 % | balance | — |
SP-700-ST — frequently asked
What is SP-700-ST used for?
SP-700-ST is typically used for superplastic-formed aerospace panels, golf club heads and biomedical devices. In short: lowest SPF temperature titanium; stronger than Ti-6Al-4V; diffusion-bonding capable sheet.
What is the yield strength of SP-700-ST?
SP-700-ST has a typical yield strength of 790 MPa (115 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 55% of titanium grades. Strength varies by condition: see the 6 listed tempers.
Is SP-700-ST easy to machine?
Not especially — machinability is rated poor (22/100, worse than 55% of titanium grades). Machine like Ti-6Al-4V but harder in STA: low surface speed (20–35 m/min carbide), heavy positive rake, rigid setup, flood high-pressure coolant, never dwell — chips are pyrophoric.
Can SP-700-ST be welded?
Yes — weldability is rated very good (70/100). GTAW, plasma, laser and electron-beam weld well with full argon/vacuum shielding and clean joints; diffusion bonding is a designed-in capability, no filler needed for SPF/DB panels.
What surface finishes work on SP-700-ST?
Pickle in HNO₃/HF to remove alpha case after hot work, then bead blast, polish or Type II colour anodize; avoid chlorinated cleaners and cadmium/mercury contact.
Can SP-700-ST be formed, bent or molded?
Superplastic at 750–800 °C with m ≈ 0.5 and >500 % elongation (about 100 °C below Ti-6Al-4V); cold bending is possible at larger radii than Ti-6Al-4V, hot form/size otherwise, then age.
What is the maximum service temperature of SP-700-ST?
SP-700-ST is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between SP-700 Annealed and SP-700-STA?
Annealed is the default condition — standard stocked condition; fine equiaxed grain for superplastic forming and best cold formability. STA: choose for maximum strength in fasteners, springs and thick sections — SP-700 hardens through much heavier sections than Ti-6Al-4V. Yield strength is 860 MPa in Annealed versus 1,150 MPa in STA.
Sources
- SP-700 High-Strength Superplastic Titanium Alloy — NKK / JFE Steel (1997)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
- Titanium alloy property records (α-β class) — MatWeb / CES EduPack (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.