Titanium Grades – Overview

Titanium (Ti) is a chemical element with atomic number 22. It is a lustrous transition metal with a silver color, low density, and high strength. Titanium is corrosion resistant in aqua regia, seawater, and chlorine.

Titanium has some properties like resistance to corrosion and strength-to-density ratio, the highest of any metallic element. In its unalloyed condition, titanium is as strong as some steels with less density.

Titanium can be alloyed with molybdenum, iron, aluminium, and vanadium, among other elements, to produce strong, lightweight alloys for aerospace, military, industrial processes, automotive, agriculture, medical prostheses, dental implants, orthopedic implants, dental and endodontic instruments and files, and other applications. Titanium can be used in various forms like titanium fasteners, pipes, tubes, bars, rods, etc.

Titanium Grade 1

Titanium Grade 1 is one of four commercially pure titanium grades. It is the softest and most ductile of these grades. It possesses the greatest formability, outstanding resistance to corrosion and high impact toughness.

Because of all these qualities, Titanium Grade 1 is the best choice for any application where ease of formability is required and is commonly available as Titanium Pipes & Tubes. These include chemical processing, chlorate manufacturing, dimensionally stable anodes, desalination, architecture, medical industry, marine industry, automotive parts, and airframe structure, etc.

Titanium Grade 2

Titanium Grade 2 is also known as the “workhorse” of the commercially pure titanium industry, thanks to its varied usability and wide availability. It shares many of the same qualities as Titanium Grade 1, but it is slightly stronger. Both are equally corrosion resistant.

Titanium Grade 2 possesses good weldability, high strength, ductility, and formability. This makes Titanium Grade 2 bar and sheet primary choice for many fields of applications: architecture, power generation, medical industry, hydrocarbon processing, marine industry, exhaust pipe shrouds, airframe skin, desalination, chemical processing, and chlorate manufacturing, etc.

Titanium Grade 3

Titanium Grade 3 is the least used commercially pure titanium grade, but that does not make it any less valuable. Titanium Grade 3 is stronger than Titanium Grades 1 and 2, similar in ductility and only slightly less formable – but it possesses higher mechanicals than its predecessors.

Titanium Grade 3 is used in applications requiring moderate strength and major corrosion resistance. These include aerospace structures, chemical processing, medical industry, marine industry, etc.

Titanium Grade 4

Titanium Grade 4 is known as the strongest of the four grades of commercially pure titanium. It is also known for its outstanding corrosion resistance, good formability, and weldability.

Titanium Grade 4 has recently found a niche as medical-grade titanium. It is needed in applications in which high strength is required: airframe components, cryogenic vessels, heat exchangers, CPI equipment, condenser tubing, surgical hardware, pickling baskets.

Titanium Grade 7

Titanium Grade 7 is mechanically and physically equivalent to Titanium Grade 2, except with the addition of the interstitial element palladium, making it an alloy. Titanium Grade 7 possesses outstanding weldability and fabricability and is the most corrosion resistance of all titanium alloys. In fact, it is most resistant to corrosion in reducing acids.

Titanium Grade 7 is used in chemical processes and production equipment components.

Titanium Grade 11

Titanium Grade 11 is very similar to Titanium Grade 1, except for the addition of a tiny bit of palladium to enhance corrosion resistance, making it an alloy. This corrosion resistance is useful to protect against crevice erosion and reducing acid in chloride environments.

Other useful properties include optimum ductility, cold formability, useful strength, impact toughness, and outstanding weldability. This alloy can be used in the same titanium applications as Titanium Grade 1, especially where corrosion is a concern such as chemical processing, chlorate manufacturing, desalination, marine applications, etc.

Ti 6Al-4V (Titanium Grade 5)

Known as the “workhorse” of the titanium alloys, Ti 6Al-4V, or Titanium Grade 5, is the most commonly used of all titanium alloys. It accounts for 50 percent of total titanium usage the world over.

Its usability lies in its many benefits. Ti 6Al-4V may be heat-treated to increase its strength. It can be used in welded construction at service temperatures of up to 600 degrees F. This alloy offers its high strength at lightweight, useful formability, and high corrosion resistance.

Ti 6AI-4V’s usability makes it the best alloy for use in several industries, like the aerospace, medical, marine, and chemical processing industries. It can be used in the creation of such technical things as Aircraft turbines, Engine components, Aircraft structural components, Aerospace fasteners, High-performance automatic parts, Marine applications, Sports equipment, etc.

Ti 6AL-4V ELI (Grade 23)

Ti 6AL-4V ELI, or Titanium Grade 23, is the higher purity version of Ti 6Al-4V. It can be made into coils, strands, wires or flat wires. It’s the top choice for any sort of situation where a combination of high strength, lightweight, good corrosion resistance, and high toughness are required. It has a superior damage tolerance to other alloys.

These benefits make Titanium Grade 23 the ultimate dental and medical titanium grade. It can be used in biomedical applications such as implantable components due to its biocompatibility, good fatigue strength, and low modulus. It can also be used in detailed surgical procedures, as:

Orthopedic pins and screws, Orthopedic cables, Ligature clips, Surgical staples, Springs, Orthodontic appliances, In joint replacements, Cryogenic vessels, Bone fixation devices.

Grade 12

Titanium Grade 12 holds an “outstanding” rating for its high-quality weldability. It is a highly durable alloy that provides high strength at high temperatures. Titanium Grade 12 possesses characteristics similar to 300 series stainless steels.

Titanium Grade 12 has high corrosion resistance which also makes it invaluable to that manufacturing equipment where crevice corrosion is a concern. Titanium Grade 12 can be used in the following industries and applications: shell and heat exchangers, hydrometallurgical applications, elevated temperature chemical manufacturing, and marine and airfare components.

Ti 5Al-2.5Sn

Ti 5Al-2.5Sn is a non-heat treatable alloy that can achieve good weldability with stability. It also possesses high-temperature stability, high strength, good resistance to corrosion and good creep resistance.

Ti 5Al-2.5Sn is mostly used in aircraft and airframe applications, as well as cryogenic applications.