Grade 5 (3.7165): Lightweight strength that is 2x stronger than Grade 2
Unlike Grade 2 which is a commercially pure titanium, Titanium Gr5 (3.7165) is a titanium alpha-beta alloy, which includes 6% aluminum (alpha stabilizer) and 4% vanadium (beta stabilizer). Also known as Ti 6Al-4V, Titanium Grade 5 is the most commonly used form of titanium, accounting for 50% of titanium worldwide. Though it offers slightly less corrosion resistance than unalloyed Grade 2, Titanium Grade 5 fasteners are critical because of their superior strength-to-weight ratio being 4 times stronger than 316 stainless steel at nearly half the weight. Compared to Grade 2,Titanium Gr5 is about 2x stronger. In addition to its strength benefits over commercially pure grades, it also provides about 60% lower thermal conductivity. Learn more about titanium grade 5 chemistry and specifications.Titanium Gr 5 Or Also Referred To As Either Ti-6Al-4V Or The Ti 6-4, Indicates The Chemical Composition Of The Alloy. Chemically, Titanium Grade 5 Fasteners Contain Almost 90% Titanium, 6% Aluminium, 4% Vanadium As Its Primary Alloying Metals.The Addition Of These Alloying Materials Makes The Titanium Gr.5 Stud Bolt Stronger. The Tensile Strength Of Ti-6al-4v Bolts Is Around 138 Ksi. Due To A High Alloying Content In Titanium Grade 5 Alloy, The Thermal Conductivity Is About 60% Lower.
Because of its high alloying content, the Ti-6al-4v Bolts are more expensive as compared to CP titanium grade 2.Addition of aluminium and vanadium in the alloy improves its physical as well as its mechanical properties by increasing the hardness of the material in the matrix of the alloy. Besides these elements, titanium grade 5 contains a maximum of each 0.25% iron and 0.2% oxygen.Features of the Titanium Gr.5 Stud Bolt include high corrosion resistance, excellent strength, low modulus of elasticity, good weldability and it is heat treatable.
Grade 5 titanium is able to withstand high temperatures, therefore it can be used at a temperature range of 400°C or 750°F.The most common industry for the Titanium Grade 5 Bolts is the aerospace industry. Since these fasteners are light in weight, grade 5 titanium is well suited to be used in aerospace applications like discs, compressor blades and rings for jet engines, pressure vessels, airframe components, rocket engine cases; helicopter rotor hubs and critical forgings requiring high strength-to-weight ratios.
The Ti-6al-4v Screws are age hardened by treating the fasteners with heat. This heat treatment given to the Titanium Gr.5 Bolts aids them in achieving even higher strengths, making them stronger. Titanium grade 5 is a biocompatible material. Hence, the Titanium Gr.5 Nuts are also well suited for medical implants. Its excellent mechanical and physical properties allow the metal to be joint with bones and other tissue.
Like CP titanium grade 2, the Titanium Grade 5 Fasteners has good resistance to corrosion to salt water and chloride compounds, although grade 2 has slightly better resistance. Titanium Gr.5 Washers is known as the alpha-beta alloy and is the workhorse alloy of the titanium industry.
Key Benefits of Titanium Gr5 Fasteners:
- Exceptional strength-to-weight ratio: making it both light weight and strong
- Extremely corrosion resistance to salt water as well as almost all chlorides
- Non-toxic, biocompatibility and osteointegration
Chemical Composition of Titanium Grade 5 Fasteners
| C | Ti | N | Fe | H | O | V | Al |
|---|---|---|---|---|---|---|---|
| 0.10 max | 90 min | 0.05 max | 0.40 max | 0.015 max | 0.20 max | 3.5-4.5 | 5.5-6.75 |
Titanium Gr5 Fasteners Mechanical Properties
| Density | Melting Point | Yield Strength (0.2%Offset) | Tensile Strength | Elongation |
|---|---|---|---|---|
| 4.43 g/cm3 | 1632 °C (2970 °F) | Psi – 128000 , MPa – 880 | Psi – 138000 , MPa – 950 | 14 % |
Salt Water Corrosion Resistance
Titanium Grade 5 fasteners offer exceptional corrosion resistance to sea water due to their oxide layer (TiO2), also called a passive layer which protects it from corrosion and forms spontaneously upon exposure to oxygen.
Because of these properties Titanium has for many years been a gold standard for salt water corrosion resistance, as it is unaffected by most marine environments including tide, splash, atmosphere and currents. Titanium is resistant to seawater up to 500F (260C) and has been shown to last almost two decades in tests of polluted seawater. In addition, Titanium Grade 5 fasteners have shown no signs of pitting and crevice corrosion even when one mile below the surface or when marine deposits form on the surface. In terms of high velocity marine environments, titanium is practically completely resistant to any erosion even up to a velocity of 120 ft./sec.
General Corrosion Resistance
In addition to salt water protection, Titanium Gr5 also resists attack by pure hydrocarbons, and most chlorinated and fluorinated hydrocarbons provided that there is no acid contamination. Titanium fasteners are also unique among metals in the chemical processing industry for handling wet chlorine gas and chlorine compounds in aqueous solutions. Titanium fasteners are also fully resistant to solutions of chlorides, hypochlorites, chlorates, perchlorates and chlorine dioxide. As a result titanium fasteners are often using within the chlorine related industries such as pulp and paper and chlor-alkali / bleach.
Though Titanium Grade 5 fasteners offer excellent resistance to sea water corrosion, they are not a good fit for corrosive applications such as hydrofluoric, hydrochloric, sulfuric and phosphoric acids, which cause the breakdown of the protective oxide layer.
Titanium Grade 5 in Medical
Titanium Gr5 (6AL4V) fasteners play a huge role in the medical field including orthopedic and dental implants, prosthetics, spinal components, and surgical instrumentation to name a few. This is due to the unique properties of this alloy.
First, Titanium Grade 5 is non-toxic and biocompatible – it is not rejected but harmonizing with the human body. Not only is able to fight off the corrosion of all body fluids, but it actually possesses a rare trait called osseointegration where the body’s natural bone and tissue actually bond to it. This feature allows Titanium Grade 5 medical implants to be firmly anchored and integrated into the body. It is also light weight and super strong – resisting fracture – which is also important to bone use. Titanium Grade 5 fasteners also give the medical community a material that has flexibility and elasticity simliar to human bone. Finally, Titanium Grade 5 fasteners are non-ferromagnetic, which allows patients with titanium medical components to be safely examined using MRIs and NMRIs.
Applications
- Aerospace relies on Titanium grade 5 for aircraft turbines, engine parts and aircraft structural components.
- Marine applications are a common place for Titanium Grade 5 due to its salt water corrosion resistance and light weight strength.
- Sports equipment and high performance automobiles use Titanium Grade 5 fasteners for their lightweight strength.
- Medical applications such as dental implants and bone replacements look to Titanium Grade 5 fasteners for their osseointegration and non-ferromagnetic properties, strength and biocompatibility.