Titanium Grade 2 vs Grade 5 (Ti-6Al-4V) — Properties and Applications

Titanium Grade 2 — Commercially Pure Titanium

Grade 2 is commercially pure (CP) titanium with a minimum 99.2% titanium content. The composition is essentially titanium with controlled levels of oxygen (max 0.25%), iron (max 0.30%), carbon, nitrogen and hydrogen as the only significant non-titanium elements.

The oxygen content is the primary strengthening element in CP titanium — Grade 1 (lowest oxygen) is the softest and most formable, while Grade 4 (highest oxygen among CP grades) is the strongest CP grade. Grade 2 sits in the middle with excellent balance of strength, corrosion resistance and formability.

Mechanical properties (ASTM B337 / B338 seamless and welded tubes): Tensile strength 344 MPa minimum, Yield strength 275 MPa minimum, Elongation 20% minimum. Density 4.51 g/cm³ — approximately 56% of steel density. Excellent cold formability — can be bent, drawn, rolled and welded without special precautions beyond titanium-specific cleanliness requirements.

Titanium Grade 5 — Ti-6Al-4V

Grade 5 is the most widely used titanium alloy worldwide, accounting for approximately 50% of all titanium usage. Its nominal composition is Titanium 90%, Aluminium 5.5–6.75%, Vanadium 3.5–4.5%, with controlled levels of Fe, O, C, N and H.

Aluminium stabilises the alpha phase and provides solid-solution strengthening. Vanadium stabilises the beta phase. The resulting alpha-beta microstructure gives Ti-6Al-4V approximately twice the strength of Grade 2 while retaining good toughness and corrosion resistance.

Mechanical properties (ASTM B265 sheet, ASTM B337 pipe, annealed condition): Tensile strength 895 MPa minimum, Yield strength 828 MPa minimum, Elongation 10% minimum. Density 4.43 g/cm³. Hardness approximately 30–36 HRC. The high strength-to-weight ratio makes Grade 5 the standard material for aerospace structural components, medical implants and high-performance engineering.

Corrosion Resistance Comparison

Both Grade 2 and Grade 5 form a stable, adherent titanium dioxide (TiO₂) passive film that provides excellent corrosion resistance in most environments. However, there are significant differences in specific environments:

Seawater and marine: Both grades perform excellently in seawater at ambient temperature. Grade 2 is actually preferred for seawater handling in desalination plants and marine heat exchangers because the lower strength does not need to be fully utilised, and Grade 2 is cheaper and more readily available in tube form.

Oxidising acids (HNO₃): Both grades are excellent. Titanium is one of the best materials for concentrated nitric acid service.

Reducing acids (HCl, H₂SO₄): Both grades have limited resistance to hot reducing acids. Grade 7 (Grade 2 + 0.12–0.25% palladium) dramatically improves reducing acid resistance and should be specified if HCl or H₂SO₄ exposure is expected.

High-temperature oxidising service: Grade 5 is preferred — it retains useful mechanical properties up to approximately 300°C in continuous service compared to Grade 2's practical limit of around 260°C.

Which Grade for Your Application

Choose Grade 2 (CP Titanium) when: Corrosion resistance in seawater, chlorides or nitric acid is the primary requirement and high mechanical strength is not needed. Applications include desalination plant condenser tubes (ASTM B338), pharmaceutical reactor vessels, seawater cooling system piping, chemical plant heat exchanger tubes and architectural cladding.

Choose Grade 5 (Ti-6Al-4V) when: High strength at low weight is the primary requirement — aerospace structural components, medical implants (ASTM F136 ELI grade for implants), automotive connecting rods, marine propeller shafts, high-performance fasteners, pressure vessel domes and sports equipment.

Choose Grade 7 (Ti-0.2Pd) when: Reducing acid environments (HCl, H₂SO₄) are present. The palladium addition dramatically expands corrosion resistance to include hot reducing acids.

Choose Grade 9 (Ti-3Al-2.5V) when: An intermediate option between Grade 2 and Grade 5 is needed — better strength than Grade 2 with better cold workability than Grade 5. Used in aerospace hydraulic tubing and bicycle frames.

Titanium Supply from Creative Metal Industries, Vadodara

Creative Metal Industries is an established supplier of titanium in India, stocking Grade 1, Grade 2, Grade 5 (Ti-6Al-4V), Grade 7 and Grade 9 in multiple product forms from approved mills including VSMPO-AVISMA (Russia), ATI Metals (USA) and Timet (USA/Europe).

Available forms: Seamless pipes and tubes (ASTM B337, B338), sheets and plates (ASTM B265), round bars and hex bars (ASTM B348), buttweld fittings (ASTM B363), forged flanges (ASTM B381), welded pipes (ASTM B338).

All titanium material supplied with EN 10204 3.1 Mill Test Certificates confirming chemistry and mechanical properties to the applicable ASTM grade. Special documentation requirements for aerospace or medical applications available on request.

For current pricing and stock availability across all titanium grades, contact Creative Metal Industries on +91 99982 80619 or visit our office at Loha Bhavan, Lakkadpitha Road, Vadodara 390001.