Titanium Fasteners
Giriraj Impex is a manufacturer, stockist, supplier and exporter of titanium fasteners in Grade 2 and Grade 5 (Ti-6Al-4V), with Grade 7 and Grade 12 on request. We manufacture titanium hex bolts, stud bolts, socket head cap screws, nuts, washers and threaded rods from ASTM B348 bar, to ASTM F468 (bolts and studs) and ASTM F467 (nuts) where specified, in imperial and metric sizes, with mill test certificates.
Titanium fasteners are used in seawater, offshore, chemical and chlorine service where steel and stainless steel bolts would corrode, and in aerospace, motorsport and other applications where the low weight and high strength of Grade 5 matter.
Specifications
| Item | Details |
|---|---|
| Bar material | ASTM B348 / ASME SB348 – Grade 2, Grade 5, Grade 7, Grade 12 |
| Fastener standards | ASTM F468 (bolts, screws, studs) and ASTM F467 (nuts) for non-ferrous fasteners |
| Products | Hex bolts, heavy hex bolts, stud bolts, threaded rods, socket head cap screws, hex and heavy hex nuts, washers |
| Dimensions | ASME B18.2.1, B18.2.2, B18.3, B16.5 stud lengths; ISO and DIN for metric fasteners |
| Threads | UNC, UNF and 8UN; ISO metric coarse and fine |
| Condition | Annealed; Grade 5 solution treated and aged on request |
| Finish | Plain, anodised or with anti-galling coating on request |
| Documents | Mill test certificate (MTC); third-party inspection on request |
Chemical composition and mechanical properties
| Grade | UNS | N | C | H | Fe | O | Al | V | Other |
|---|---|---|---|---|---|---|---|---|---|
| Grade 1 | R50250 | 0.03 | 0.08 | 0.015 | 0.20 | 0.18 | – | – | – |
| Grade 2 | R50400 | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | – | – | – |
| Grade 5 | R56400 | 0.05 | 0.08 | 0.015 | 0.40 | 0.20 | 5.5–6.75 | 3.5–4.5 | – |
| Grade 7 | R52400 | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | – | – | Pd 0.12–0.25 |
| Grade 12 | R53400 | 0.03 | 0.08 | 0.015 | 0.30 | 0.25 | – | – | Mo 0.2–0.4, Ni 0.6–0.9 |
Hydrogen limits differ slightly between product forms; residual element limits as given in each ASTM specification.
| Grade | Tensile strength, MPa (ksi) | Yield strength 0.2%, MPa (ksi) | Elongation, % |
|---|---|---|---|
| Grade 1 | 240 (35) | 138 (20) | 24 |
| Grade 2 | 345 (50) | 275 (40) | 20 |
| Grade 5 | 895 (130) | 828 (120) | 10 |
| Grade 7 | 345 (50) | 275 (40) | 20 |
| Grade 12 | 483 (70) | 345 (50) | 18 |
Grades 1, 2 and 7 also have maximum yield strength limits. Values are typical of ASTM B265 and B348; check the specification for the product form.
Fasteners keep the composition and properties of the bar from which they are made. Background is on the titanium page.
Grade 2 or Grade 5 fasteners?
Grade 2 fasteners are commercially pure titanium, used where corrosion resistance is the main need and loads are moderate: bolting for titanium equipment and piping in chemical, chlorine and bleach plants, fasteners for anodes and electrolytic cells, and fixings in seawater and marine structures.
Grade 5 (Ti-6Al-4V) fasteners have more than twice the strength of Grade 2, with a minimum tensile strength of about 895 MPa, while weighing about 43% less than steel bolts of the same size. They are used for high-strength corrosion-resistant bolting offshore and subsea, in aerospace and motorsport, for marine propulsion and for lightweight structures. In the solution-treated and aged condition, Grade 5 reaches even higher strength.
Galvanic considerations
Titanium is a noble metal in seawater. When titanium bolts fasten parts made of less noble metals, such as carbon steel or aluminium, the small bolt area is protected and the larger part sees only slight extra corrosion – an acceptable combination in many cases. The reverse – steel bolts in titanium parts – should be avoided, as the steel bolts corrode rapidly. Insulating washers and sleeves can be used where a dissimilar-metal joint must be isolated.
How we manufacture titanium fasteners
We manufacture titanium fasteners from certified B348 bar. Bolts are hot forged or machined; threads are rolled or cut, with rolled threads preferred for fatigue strength; nuts are machined from hexagonal or round bar. Titanium has low thermal conductivity and can gall on tools, so machining uses sharp tools, low speeds and plenty of coolant. Each fastener is marked with grade and heat number, thread gauged and inspected, and supplied with the mill test certificate of the bar.
Galling and installation
Titanium threads gall readily when titanium nuts are tightened on titanium bolts. Anti-seize compounds suitable for titanium, anodised or coated threads, and steady tightening reduce the risk. Avoid compounds containing chlorides or other substances that may attack titanium at high temperature. Calculate tightening torque for the lubricant and grade, not from steel tables.
Ordering titanium fasteners
Please give the grade, fastener type, diameter and thread, length, number of nuts per stud, washers, condition, finish, quantity and any testing or inspection requirement. For flange bolting, give the flange size, class and facing and we can calculate stud lengths.
Applications and related products
Titanium fasteners are used in offshore and subsea equipment, seawater systems, desalination, chlor-alkali and bleach plants, chemical processing, anodes and electrolytic cells, marine engineering, aerospace and motorsport. Matching products include titanium flanges, titanium pipe fittings, titanium pipes and tubes, titanium sheets and plates and titanium round bars. Fasteners in other materials are on the fasteners page.
Frequently Asked Questions
ASTM F468 covers non-ferrous bolts, screws and studs and ASTM F467 covers non-ferrous nuts, including titanium grades. Bar is to ASTM B348.
Grade 2 is commercially pure titanium for corrosion resistance at moderate loads. Grade 5 (Ti-6Al-4V) has more than twice the strength for high-load applications.
Titanium has a density of about 4.4–4.5 g/cm³, so titanium bolts weigh about 43% less than steel bolts of the same size.
Yes, titanium-on-titanium threads gall readily. Suitable anti-seize compounds, anodised or coated threads and steady tightening reduce the risk.
Titanium bolts in steel or aluminium parts are usually acceptable, as the noble bolt is protected. Steel bolts in titanium parts should be avoided.
Yes. Titanium fasteners are supplied in imperial and ISO metric sizes to ASME, ISO and DIN dimensions.
Request a Quote for Titanium Fasteners
Tell us the product, grade, size, standard, quantity and delivery location, and our sales team will reply with a quotation.