Titanium Grade 7 · temper · default condition
Titanium Grade 7-O
Properties of the O condition, compared with the other Grade 7 tempers.
Standard stocked condition for all corrosion-service product forms; best ductility and formability.
What is Grade 7-O?
Grade 7-O is Grade 7 in the O temper — standard stocked condition for all corrosion-service product forms; best ductility and formability. Grade 7-O has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 87% of titanium grades. Elongation at break is 24% and the elastic modulus is 103 GPa (14.9 Msi). Grade 7-O has a density of 4.51 g/cm³ (0.163 lb/in³), heavier than 57% of titanium grades. It melts at 1,665°C (3,029 °F).
Advantages
- Forms and bends easily — 75/100, better than 83% of titanium grades
- Easy to machine — 35/100, better than 78% of titanium grades
- Ductile — tolerates forming and impact — 24%, better than 77% of titanium grades
- High electrical conductivity — 3.1 % IACS, better than 75% of titanium grades
Limitations
- Low strength — 320 MPa (46.4 ksi), worse than 87% of titanium grades
Grade 7-O properties
Typical room-temperature values for Grade 7-O — 14 properties are specific to this condition; the rest are grade-level values shared by every Grade 7 temper. Each bar shows where the value sits among the titanium grades in FabDigit's library — further right is higher.
Physical3
Grade 7-O has a density of 4.51 g/cm³ (0.163 lb/in³), heavier than 57% of titanium grades. It melts at 1,665°C (3,029 °F).
Mechanical16
Grade 7-O has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 87% of titanium grades. Elongation at break is 24% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
Grade 7-O is rated for continuous service to 315°C (599 °F). It conducts heat at 16.4 W/m·K (9.48 BTU/hr·ft·°F), better than 71% of titanium grades. Thermal expansion is 8.6 µm/m·K (4.78 µin/in·°F).
Electrical3
Grade 7-O conducts electricity at 3.1 % IACS, better than 75% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (96/100), better than 92% of titanium grades.
Sustainability4
Producing a kilogram of Grade 7-O takes about 700 MJ of energy and emits 45 kg of CO₂ — more than 74% of titanium grades. Typical recycled content is 25%.
Manufacturability8
Grade 7-O's machinability is fair (35/100, better than 78% of titanium grades); weldability excellent (85/100); formability very good (75/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Grade 7 tempers and conditions
Grade 7 is also supplied in 2 other conditions. The full side-by-side table is on the Grade 7 overview.
- ODefaultStandard stocked condition for all corrosion-service product forms; best ductility and formability.320 MPa yield · 160 HB
- CWPick when higher strength or tighter dimensional tolerance is needed from bar, wire or small tube; ductility and formability drop.480 MPa yield · 215 HB
Working with Grade 7-O
Is Grade 7 easy to machine?
Machine like CP Ti Gr.2: rigid setup, sharp uncoated/ TiAlN carbide, low surface speed (25–45 m/min), heavy flood coolant, avoid dwell to prevent galling and work hardening.
Can Grade 7 be welded?
Excellent GTAW/GMAW/PAW/EB/resistance weldability using matching Gr.7 (ERTi-7) filler; requires full argon shielding of pool, trailing and back-purge, clean oxide-free prep, and colour checks — as-welded joints keep Pd-enhanced corrosion resistance.
Can Grade 7 be formed, bent or molded?
Cold form at generous bend radii (≈2–3 t) with allowance for springback; warm forming 200–400 °C eases severe draws; annealed sheet deep-draws similarly to Gr.2.
What surface finishes work on Grade 7?
Pickle in HNO₃/HF then rinse to restore the passive film; can be colour anodized (AMS 2488), glass-bead or electropolished; avoid iron contamination and steel wire brushing.
Grade 7 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 |
|---|---|---|
| Pdcorrosion-enhancing addition | 0.12 – 0.25 | 0.18 |
| Fe | ≤ 0.3 | 0.15 |
| O | ≤ 0.25 | 0.15 |
| C | ≤ 0.08 | 0.02 |
| N | ≤ 0.03 | 0.01 |
| H0.0125 max for some tube/plate forms | ≤ 0.02 | 0.01 |
| Other, eachresidual elements | ≤ 0.1 | — |
| Other, totalresidual elements | ≤ 0.4 | — |
| Ti | balance | — |
Grade 7-O — frequently asked
What is Grade 7-O used for?
Grade 7-O is typically used for hot acid pipework and pumps, pulp bleaching plant equipment, chlorine-dioxide and brine service vessels, heat exchanger tubing for reducing acids, chemical reactor internals and liners and anodes and electrolytic cell hardware. In short: palladium corrosion-proof titanium.
What is the yield strength of Grade 7-O?
Grade 7-O has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 87% of titanium grades. Strength varies by condition: see the 3 listed tempers.
Is Grade 7-O easy to machine?
Not especially — machinability is rated fair (35/100, better than 78% of titanium grades). Machine like CP Ti Gr.2: rigid setup, sharp uncoated/ TiAlN carbide, low surface speed (25–45 m/min), heavy flood coolant, avoid dwell to prevent galling and work hardening.
Can Grade 7-O be welded?
Yes — weldability is rated excellent (85/100). Excellent GTAW/GMAW/PAW/EB/resistance weldability using matching Gr.7 (ERTi-7) filler; requires full argon shielding of pool, trailing and back-purge, clean oxide-free prep, and colour checks — as-welded joints keep Pd-enhanced corrosion resistance.
What surface finishes work on Grade 7-O?
Pickle in HNO₃/HF then rinse to restore the passive film; can be colour anodized (AMS 2488), glass-bead or electropolished; avoid iron contamination and steel wire brushing.
Can Grade 7-O be formed, bent or molded?
Cold form at generous bend radii (≈2–3 t) with allowance for springback; warm forming 200–400 °C eases severe draws; annealed sheet deep-draws similarly to Gr.2.
What is the maximum service temperature of Grade 7-O?
Grade 7-O is rated for continuous use to about 315°C (599 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Grade 7-O and Grade 7-CW?
O is the default condition — standard stocked condition for all corrosion-service product forms; best ductility and formability. CW: pick when higher strength or tighter dimensional tolerance is needed from bar, wire or small tube; ductility and formability drop. Yield strength is 320 MPa in O versus 480 MPa in CW.
Can FabDigit make parts in Grade 7-O?
Yes — Grade 7-O is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B265 — Titanium and Titanium Alloy Strip, Sheet, and Plate — ASTM International (2020)
- ASTM B348 — Titanium and Titanium Alloy Bars and Billets — ASTM International (2021)
- ASTM B338 — Seamless and Welded Titanium and Titanium Alloy Tubes for Condensers and Heat Exchangers — ASTM International (2017)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- Titanium Grade 7 / Ti-0.2Pd corrosion and mechanical data — TIMET / ATI (2018)
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.