Titanium C-1
ASTM B367 Grade C-1
C-1 is the unalloyed titanium investment casting grade of ASTM B367, the cast counterpart of wrought CP Grade 1 and the lowest-strength, highest-ductility member of the cast CP family.
Reference datasheet — C-1 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the F condition
C-1 tempers and conditions
C-1 is supplied in 3 conditions, soft to hard. F is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Use when machining distortion or residual stress from casting/weld repair must be removed; slightly lower strength, maximum ductility. | 200 | 290 | 24 | 115 HB | 3.6 % IACS |
FDefault As fabricated | Standard stocked/supplied condition for chemical-process and marine castings; meets B367 C-1 minima without HIP. | 210 | 300 | 20 | 120 HB | 3.6 % IACS |
Hot isostatic pressed | Pick when internal porosity must be closed for fatigue-loaded, pressure-boundary or medical castings; same tensile minima, better ductility and fatigue scatter. | 215 | 310 | 25 | 120 HB | 3.6 % IACS |
What is C-1?
C-1 is the unalloyed titanium investment casting grade of ASTM B367, the cast counterpart of wrought CP Grade 1 and the lowest-strength, highest-ductility member of the cast CP family. It provides 210 MPa yield, 300 MPa tensile, 20 % elongation and 120 HB with service to 300 °C, and is poured as valve bodies, pump housings and other complex corrosion-resistant shapes. Choose it where corrosion resistance and formability outweigh strength; where more load capacity is needed in the same chemistry, move to C-2 or C-4. Castings carry an alpha case that must be removed, and weld repair is standard practice under B367. C-1 has a density of 4.51 g/cm³ (0.163 lb/in³), heavier than 57% of titanium grades. It melts at 1,660°C (3,020 °F). C-1 has a yield strength of 210 MPa (30.5 ksi) and a tensile strength of 300 MPa (43.5 ksi) — weaker than 99% of titanium grades. Elongation at break is 20% and the elastic modulus is 103 GPa (14.9 Msi).
What is C-1 used for?
- chemical process valve bodies
- corrosion-resistant pump housings
- marine hardware castings
- architectural fittings
Advantages
- High electrical conductivity — 3.6 % IACS, better than 98% of titanium grades
- Easy to machine — 42/100, better than 98% of titanium grades
- Conducts heat well — 17 W/m·K (9.82 BTU/hr·ft·°F), better than 84% of titanium grades
Limitations
- Low strength — 210 MPa (30.5 ksi), worse than 99% of titanium grades
C-1 properties
Typical room-temperature values for C-1-F; bars are the position among titanium grades.
Physical3
C-1 has a density of 4.51 g/cm³ (0.163 lb/in³), heavier than 57% of titanium grades. It melts at 1,660°C (3,020 °F).
Mechanical16
C-1 has a yield strength of 210 MPa (30.5 ksi) and a tensile strength of 300 MPa (43.5 ksi) — weaker than 99% of titanium grades. Elongation at break is 20% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
C-1 is rated for continuous service to 300°C (572 °F). It conducts heat at 17 W/m·K (9.82 BTU/hr·ft·°F), better than 84% of titanium grades. Thermal expansion is 8.6 µm/m·K (4.78 µin/in·°F).
Electrical3
C-1 conducts electricity at 3.6 % IACS, better than 98% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (93/100), better than 72% of titanium grades.
Sustainability4
Producing a kilogram of C-1 takes about 640 MJ of energy and emits 40 kg of CO₂ — less than 93% of titanium grades. Typical recycled content is 30%.
Manufacturability8
C-1's machinability is fair (42/100, better than 98% of titanium grades); weldability excellent (88/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the titanium family
Yield strength against density for every titanium grade FabDigit runs. C-1 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C-1
Is C-1 easy to machine?
Low speed, high feed, rigid setup, flood coolant and sharp carbide/uncoated tools; CP Ti is gummy and work-hardens, avoid dwelling and never rub — fine chips are a fire hazard.
Can C-1 be welded?
Excellent GTAW/EBW/plasma weldability with matching or no filler, but requires full argon/vacuum shielding of weld, root and cooling zone to <500 °C to avoid embrittlement; weld repair of castings is standard and covered by B367.
Can C-1 be formed, bent or molded?
Produced by vacuum-arc melting plus rammed-graphite or ceramic-shell investment casting; expect an alpha-case layer that must be chemically milled or machined off, and allow generous fillets/feeders because of low fluidity.
C-1 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 |
|---|---|---|
| Nmax per ASTM B367 Grade C-1 | ≤ 0.05 | 0.02 |
| C | ≤ 0.1 | 0.03 |
| H | ≤ 0.02 | 0.01 |
| Fe | ≤ 0.2 | 0.08 |
| Omax; controls strength level of C-1 | ≤ 0.18 | 0.12 |
| residuals eachother elements, each | ≤ 0.1 | |
| residuals totalother elements, total | ≤ 0.4 | |
| Ti | balance |
What surface finishes work on C-1?
Grit blast + pickle (HNO3/HF) to remove alpha case, then optional passivation, colour anodizing for identification, or plasma/grit-blast texturing for medical parts; do not use chloride-rich markers or lead-bearing pastes before heating.
Surface treatments FabDigit runs on titanium parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Titanium C-1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B367 Grade C-1
How much does C-1 cost?
C-1 is a high-cost titanium ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C-1 — frequently asked
What is C-1 used for?
C-1 is typically used for chemical process valve bodies, corrosion-resistant pump housings, marine hardware castings and architectural fittings. In short: most ductile cast titanium; cast CP Grade 1 equivalent; corrosion-first casting grade.
What is the yield strength of C-1?
C-1 has a typical yield strength of 210 MPa (30.5 ksi) and a tensile strength of 300 MPa (43.5 ksi) — weaker than 99% of titanium grades. Strength varies by condition: see the 3 listed tempers.
Is C-1 easy to machine?
Not especially — machinability is rated fair (42/100, better than 98% of titanium grades). Low speed, high feed, rigid setup, flood coolant and sharp carbide/uncoated tools; CP Ti is gummy and work-hardens, avoid dwelling and never rub — fine chips are a fire hazard.
Can C-1 be welded?
Yes — weldability is rated excellent (88/100). Excellent GTAW/EBW/plasma weldability with matching or no filler, but requires full argon/vacuum shielding of weld, root and cooling zone to <500 °C to avoid embrittlement; weld repair of castings is standard and covered by B367.
What surface finishes work on C-1?
Grit blast + pickle (HNO3/HF) to remove alpha case, then optional passivation, colour anodizing for identification, or plasma/grit-blast texturing for medical parts; do not use chloride-rich markers or lead-bearing pastes before heating.
Can C-1 be formed, bent or molded?
Produced by vacuum-arc melting plus rammed-graphite or ceramic-shell investment casting; expect an alpha-case layer that must be chemically milled or machined off, and allow generous fillets/feeders because of low fluidity.
What is the maximum service temperature of C-1?
C-1 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 C-1-F and C-1-ANN?
F is the default condition — standard stocked/supplied condition for chemical-process and marine castings; meets B367 C-1 minima without HIP. ANN: use when machining distortion or residual stress from casting/weld repair must be removed; slightly lower strength, maximum ductility. Yield strength is 210 MPa in F versus 200 MPa in ANN.
How much does C-1 cost?
C-1 is a high-cost titanium ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B367 — Standard Specification for Titanium and Titanium Alloy Castings — ASTM International (2022)
- ASTM B265 / ASTM B348 — CP Titanium Grade 1 wrought product (property comparison) — ASTM International (2020)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Titanium) — ASM International (1990)
- ASM Handbook Vol. 19 — Fatigue and Fracture (titanium castings) — ASM International (1996)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.