Which is better, grade 2 or grade 5 titanium?

29 Apr.,2024

 

Titanium Grade 5 vs Titanium Grade 2 Comparison

Technical Resources

Titanium Grade 5 vs Titanium Grade 2

Comparison between the alpha-beta alloy and the workhorse of commercially pure grade

 

For more information, please visit our website.

 

Ti 6Al-4V is the most widely used of all Titanium grades. It is typically available in the annealed condition and is readily heat treatable to increase strength, for a wide range of applications. As a general-purpose alloy, Ti 6Al-4V has a broad spectrum of desirable properties at temperatures around -210°C – 400°C.

Titanium grade 5 or Ti 6Al-4V is an alpha-beta (α-β) alloy. Therefore, it may be heat treated to give medium-high strength in sections under 100 mm thick. However, hardenability is limited and sections over 25 mm may not fully develop desired properties. Ti 6Al-4V has a good weldability (with matching or ELI filler wire) and hot-formability. The degree of cold forming is, however, limited.

Titanium grade 1 is the most ductile of the commercially pure Titanium grades. As a result, the alloy is widely specified for the manufacture of plate heat exchangers.

 

Titanium Grade 2 or Titanium CP3 is a commercially pure alpha (α) alloy. Although not as strong as Ti 6Al-4V, Titanium grade 2 has outstanding corrosion resistance against variety of aggressive media. For example, Titanium grade 2 is virtually immune to wet chlorine at 10°C – 80°C (0-0.02 mpy or 0.001 mm/y) and thus, used to make chlorine dioxide mixers, pipework and fasteners in modern bleach plants.

Titanium grade 2 is specified based on its excellent corrosion resistance in environments which include: calcium chloride, cupric chloride, ferric chloride, various concentrations of acetic acid, high temperature seawater, most organic media and more.
However, other conditions such as temperature, pH level and flow velocity could alter its properties drastically e.g. susceptibility to stress corrosion cracking and crevice corrosion. When compared with Titanium grade 5 (Ti 6Al-4V), Titanium grade 2 is generally selected where aqueous corrosion resistance and/or formability are required.

Properties Ti 6Al-4V (UNS R56400) Titanium Grade 2 (UNS R50400) Metallurgy 895 MPa 345 MPa Ultimate tensile strength 827 MPa 276 MPa 0.2% offset yield strength 827 MPa 276 MPa % Elongation (Ductility) 10 20 Corrosion resistance Very good Outstanding Creep and stress-rupture High NA Fatigue High NA Service temperature -210°C – 400°C for reliable structural integrity Depends on environments e.g. up to 316°C for steam and seawater Weldability Weldable

At temperatures up to 200°C in normal atmosphere, Titanium grade 2 and other commercially pure grades are also a popular choice for lining material, when corrosion resistance is needed on the surface. Often cheaper and stronger steels are used as outer assemblies. One key application is lining of chimney stacks on coal fired power stations which have been retrofitted with FGD Systems ( Flue Gas Desulphurisation plants).

Titanium Grades: How to Choose the Right Grade

You’ve done your research and determined that titanium is the correct metal for your next product. This, however, is just the first step. There are still a couple important decisions that need to be made.

There are multiple grades of commercially pure titanium and titanium alloys, and you need to be sure that you get the right forms and grades to ensure your project is completed successfully.

While all grades are corrosive resistant, strong and lightweight, there are still some significant differences that could impact the final results. When you choose the titanium grade, it’s important to consider how the metal will be used, what conditions the titanium will be in, and the size of the titanium parts.

Pure grade titanium comes in four grades, each with different characteristics that make them ideal for different projects.

Below is a list of commercially pure titanium and many of the most common alloys, including the common product forms and usages. Understanding these traits and how they can impact your project can help you choose the right titanium grade for the job.

 

Commercially Pure Titanium Grades 
Grade 1

Grade 1 titanium is the softest grade of titanium, which makes it very formable. It offers a high ductility while still maintaining the necessary impact toughness. This grade is most often used in plates, tubing, piping, and a range of other applications where a higher level of weldability and formability is important.

This titanium is used in a variety of industries and its characteristics make it an effective choice for:

Goto GIANT ANODE to know more.

  • aerospace
  • medical
  • marine
  • architecture
  • manufacturing
  • power
  • chemical processing facilities
  • desalination
  • automotive parts
  • airplane structures and frames
Grade 2

For slightly stronger metal, there is Grade 2 titanium. It is still very moldable, but has a higher tensile strength. Grade 2 titanium is very widely available, which makes it more affordable than other grades. The common product forms include everything from bar and billet to plate and wire.

It has many of the same applications as grade 1 titanium, though it is also used in:

  • power generation
  • hydro-carbon processing
  • exhaust pipe shrouds
  • airframe skin
Grade 3

Grade 3 titanium is not used near as much as grade 2, but it still has its uses. It is stronger than grades 1 and 2, features good weldability, and extremely high corrosion resistance. It is less moldable than the other 2 grades, but the added strength and resistance make it a good choice for:

  • chemical processing
  • marine applications
  • aerospace

It can be purchased in bar, billet, ingot. plate, and welded products.

Grade 4

Grade 4 titanium is the strongest pure grade titanium, but it is also the least moldable. Still, it has a good cold formability, and it has many medical and industrial uses because of its great strength, durability and weldability. Grade 4 titanium is most commonly found in:

  • surgical hardware
  • heat exchangers
  • CIP equipment

It can be purchased in bar, billet, ingot, plate, and strip.

Titanium Alloys

Titanium alloys are a mixture of titanium and one or two other metals, such as tin, palladium, silicon, vanadium, molybdenum, zirconium, manganese, iron, cobalt, nickel, copper and chromium. Titanium alloys have the same strength, corrosion resistance, durability and light weight as commercially pure titanium, but by creating these alloys, it’s possible to build on and enhance certain characteristics.

Grade 5 (Ti 6Al-4V) Titanium

Ti 6AI-4V (a.k.a grade 5) is the most common of titanium alloys, and it referred to as the “workhorse” of the aerospace industry for a reason. It can resist temperatures up to 600 degrees Fahrenheit, is strong, light-weight, highly formable, and extremely corrosion resistant. It is made from the combination of titanium, aluminum, vanadium, and iron.

Grade 5 is popular in the aerospace industry for aircraft turbines as well as structural components, but it is also used in high-performance engine parts, sports equipment biomedical implants, and more. Common product forms include bar, billet, foil, sheet, seamless pipe, wire, plate and more.

Grade 7

Grade 7 is the most corrosion resistant of the titanium alloys. It features most of the properties of grade 2 pure titanium, but the added palladium helps increase the weldability and formability. It is most commonly used in chemical production equipment, and is available in most product forms.

Grade 12

Grade 12 has a strength that is similar to the 300 series steels, and it has a very high formability and weldability, making it a good choice for various fabricated applications. Its high corrosion resistance also makes it a common choice for:

  • heat exchanges
  • chemical manufacturing
  • marine applications
  • aerospace applications

It can be purchased in bar, billet, plate, strip, wire, and welded pipe and tubing.

Grade 23 (Ti 6AL-4V ELI) Titanium

Ti 6AL-4V ELI, or Grade 23, has is often made into coils, strands, wires or flat wires. It is made of a combination of titanium, vanadium and aluminum, which gives it a very high tensile and yield strength while reducing the ductility and weldability. It also has a unique biocompatibility property that makes it popular for many medical and dental applications including:

  • surgical staples
  • ligature clips
  • pins and screws
  • and more

It has also found work in airframe components and ballistic armor. It is available in most common product forms, including seamless pipe and tubing.

Other Titanium Alloys

Though the most common titanium alloys were listed above, there are many other, less known and used titanium alloys. Titanium alloys go all the way up to grade 38, and their characteristics and applications vary based on the alloy metals.

When determining what grade of titanium or titanium alloy that would be right for your project, consider the environment it will be in, what the part will do, and the size of the desired part.

If you have additional questions or you’re ready to make your titanium or titanium alloy order, contact Titanium Processing Center today.

For more information, please visit titanium sheet supplier.