Titanium Round Bar Overview
Titanium round bar is a solid circular-section product supplied in straight lengths for applications that need low density, high specific strength and outstanding corrosion resistance at the same time. With a density of roughly 4.51 g/cm3 it weighs about 43 percent less than an equal volume of steel, yet commercially pure grades still deliver tensile strength in the 240-740 MPa range depending on grade and supplied condition.
The metal resists chlorides, seawater, oxidising acids and most industrial chemicals because a thin self-repairing titanium dioxide layer forms spontaneously on the surface. That passive film is why titanium round bar performs reliably in chemical processing, desalination and marine service where carbon steel and even stainless steel would pit or suffer stress-corrosion cracking.
Grades and Standards
Round bar is produced to ASTM B348 for titanium and titanium alloy bars and billets, and to GB/T 2965 for domestic supply. The two systems overlap closely but are not identical in chemistry, so a grade designation is always stated together with the standard to which it is ordered.
Commercially pure grades - ASTM Gr1, Gr2, Gr3 and Gr4, with equivalent GB TA0, TA2 and TA3: rising oxygen and iron content increases strength while slightly reducing ductility. Gr2 is the general-purpose workhorse.
Corrosion-resistant grades - ASTM Gr7, Gr11 and Gr12, with GB TA9 and TA10: palladium or molybdenum additions extend service life in reducing acids and high-chloride brines.
Alpha-beta alloys - ASTM Gr5 (Ti-6Al-4V) with GB TC4, and ASTM Gr9 (Ti-3Al-2.5V) with GB TA18: heat-treatable alloys reaching tensile strength above 895 MPa for aerospace and high-load components.
Size Range and Dimensional Options
| Parameter | Range | Notes |
|---|---|---|
| Diameter | 0.1 mm - 600 mm | Drawn small bar up to large forged billet |
| Length | 1 m, 2 m, 3 m, 6 m | Random or fixed cut lengths |
| Straightness | 1 mm per metre typical | Improved by cold drawing and roller straightening |
| Surface | Pickled, turned, ground, polished | Bright finish for automatic machining |
| Condition | Annealed, hot worked, cold worked | Matched to the forming operation |
Manufacturing Techniques
Three process routes cover most demand. Hot forging breaks down the cast ingot structure and produces large diameter bar with refined grain flow. Hot rolling suits medium diameters where a sound surface and reasonable dimensional control are required at lower cost. Cold drawing, usually combined with intermediate annealing, delivers the tightest diameter tolerance, the best straightness and the brightest finish, and is the normal route for small bar destined for automatic screw machines.
Every route ends with ultrasonic inspection, chemical analysis and mechanical testing before dispatch, and the mill test certificate traces the heat number back to the melt.
Applications by Industry
Chemical and petrochemical: heat exchanger tubesheets, pump shafts, valve stems and reactor internals exposed to chloride-bearing media.
Medical: bone screws, spinal rods, dental abutments and instrument shafts, mainly in Gr5 and Gr23 ELI compositions.
Aerospace: fasteners, actuator components and airframe fittings where specific strength governs design.
Marine and desalination: seawater piping, subsea hardware and condenser components.
Electronics and metallurgy: anodes, sputtering targets and vacuum chamber parts.
How Elemental Content Changes Performance
Oxygen is the most influential interstitial in commercially pure titanium. Raising it from about 0.18 percent in Gr2 to 0.40 percent in Gr4 lifts tensile strength from roughly 345 MPa to 550 MPa while ductility falls. Iron and nitrogen strengthen in the same direction but also reduce toughness. Aluminium stabilises the alpha phase and raises high-temperature strength, vanadium stabilises beta and improves hardenability, while palladium and ruthenium are added purely for corrosion resistance. Because these effects are additive, composition is specified tightly rather than left to the ingot producer.
Frequently Asked Questions
Q: Can custom diameters and lengths be produced?
Yes. Bar outside the standard range is produced to order, including intermediate diameters, fixed cut lengths and closer tolerances.
Q: Which grades are normally held in stock?
Gr2, Gr5 and Gr7 round bar are usually available from stock in common diameters; other grades and sizes are produced to order.
Q: What is the maximum length available?
Standard mill lengths are 1 m, 2 m, 3 m and 6 m. Longer single pieces depend on diameter and process route and are agreed before production starts.
Q: Is titanium round bar suitable for high-temperature service?
Commercially pure grades work continuously up to about 300 degrees C in oxidising conditions, and alloys such as Gr5 retain useful strength to roughly 400 degrees C. Above those limits oxidation accelerates and creep becomes significant.
Q: How does titanium compare with stainless steel 316?
Titanium is about 40 percent lighter, tolerates chlorides without pitting and resists seawater far better, but it costs more per kilogram and requires slower machining speeds.
Q: What surface finishes are available?
Pickled, turned, centreless ground and polished finishes are all supplied; ground bar is preferred when parts are machined on automatic lathes.
