Standard Specification for Titanium and Titanium Alloy Castings
ASTM B367 covers titanium and titanium alloy castings produced by investment casting, centrifugal casting, or other approved methods. These castings are intended for aerospace, medical, marine, chemical, and industrial applications, including structural and pressure-containing parts.
Applicable Grades (UNS Designations)
Grade |
UNS Number |
Description |
Gr C-1 |
J50250 |
CP titanium, similar to wrought Gr 2 |
Gr C-2 |
J50350 |
CP titanium, similar to wrought Gr 3 |
Gr C-3 |
J50460 |
CP titanium, similar to wrought Gr 4 |
Gr C-4 |
J50550 |
CP titanium, high strength CP |
Gr C-5 |
J50605 |
Ti-6Al-4V, general-purpose alloy |
Gr C-6 |
J50610 |
Ti-5Al-2.5Sn, aerospace use |
Gr C-7 |
J50611 |
Ti-6Al-4V ELI, improved ductility, medical use |
Gr C-8 |
J50612 |
Ti-6Al-6V-2Sn, higher strength |
Gr C-12 |
J50614 |
Ti-0.3Mo-0.8Ni, corrosion-resistant |
Custom compositions are permitted by agreement.
Manufacturing Processes
Investment casting (lost-wax): Most common method for precision parts
Centrifugal casting: Often used for tubular parts
Other methods: Allowed with purchaser approval
Heat treatment is mandatory for most grades to develop mechanical properties. Methods include:
Annealing
Solution treatment and aging (STA)
Stress relieving (as required)
Mechanical Properties (Typical Minimums)
Grade |
UTS (MPa) |
YS (MPa) |
Elongation (%) |
Reduction of Area (%) |
C-5 (Ti-6Al-4V) |
≥ 895 |
≥ 825 |
≥ 4 (castings) |
≥ 10 |
C-7 (Ti-6Al-4V ELI) |
≥ 860 |
≥ 795 |
≥ 6 |
≥ 15 |
C-12 (Ti-0.3Mo-0.8Ni) |
≥ 485 |
≥ 345 |
≥ 18 |
≥ 25 |
Note: Actual values depend on the casting shape, heat treatment, and section thickness.
Dimensional Tolerances
As per customer drawings or investment casting industry standards.
Typically, linear tolerances ±0.5 mm to ±1.5 mm depending on size and complexity.
Surface finish: 3.2–6.3 μm Ra (125–250 μin) typical.
Inspection and Testing
Chemical Analysis: Per ASTM E539 / E2922 or equivalent.
Mechanical Testing: Tensile test on separately cast or integrally cast test bars.
Non-Destructive Testing (NDT): Visual + optional RT, PT, UT (especially aerospace/medical).
Dimensional Inspection: Per drawing/spec; includes shrinkage allowances.
Test bars must represent the final heat-treated condition of the casting.
Marking Requirements
Each casting must be marked with:
Manufacturer's name or trademark
ASTM B367
Grade designation
Heat number or melt identification
Optional: serial number or part number
Mill Test Report (MTR) must include:
Chemical analysis
Mechanical test results
NDT results (if performed)
Heat treatment record
Related Standards
ASTM F1108-Ti-6Al-4V castings for surgical implants
ASTM F1472-Wrought Ti-6Al-4V (comparison standard)
AMS 4991-Aerospace casting spec for Gr C-5