Grade 2 titanium is a popular choice for commercial use
due to its strength, durability, and corrosion resistance. This grade of
titanium has a minimum yield strength of 275 MPa and a minimum ultimate tensile
strength of 450 MPa, making it one of the strongest grades of commercially pure
titanium. The strain hardening is eliminated during 600°C annealing. Hence,
relatively lower strength and better ductility are obtained. Usually for grade
2 titanium tubes, the annealing temperature should be at 600°C. The annealing process
is a heat treatment of titanium that changes the physical and sometimes
also the chemical properties to reduce the hardness to make it more workable. The
purpose of annealing is to improve the grade 2 titanium machinability.
This grade of titanium is commonly used in the aerospace,
automotive, and medical industries due to its ability to withstand high
temperatures and harsh environments. It is also widely used in the construction
industry for its corrosion resistance, making it a popular choice for outdoor
structures and infrastructure. Examples of how titanium can be used to
structural repair of historic buildings include the Guggenheim Museum, Bilbao which
is sheathed in Titanium panels. Titanium was used as a part of the 2008
structural repair and stabilization for the Leaning tower of Pisa in Italy.
In addition to its strength and corrosion resistance,
grade 2 titanium is also biocompatible, making it suitable for use in medical
implants and devices. It is also non-toxic and non-allergenic, making it a safe
choice for use in food processing and handling equipment. Grade 2 titanium is
the main unalloyed titanium used in dental implant applications.
Titanium, specifically grade 2, is biocompatible because
it has a low electrical conductivity which contributes to the electrochemical
oxidation of titanium leading to the formation of a thin passive oxide layer. Titanium
alloys are used in biomedical implant devices which replace damaged hard
tissue. Some examples of titanium use in biomedical applications are dental and
orthopedic implants, artificial hearts, pacemakers, artificial knee joints,
bone plates, cardiac valve prostheses, screws for fracture fixation, artificial
hip joints and cornea backplates. Titanium and titanium alloys have therefore
been used widely as biomedical implant materials since the early 1970s and the
implants have been available as machined and cast components.
Grade 2 titanium is a versatile and reliable material
that is widely used in a variety of commercial applications as well due to its
strength and durability. Additionally, grade 2 titanium is lightweight, yet
strong, making it a popular choice for automotive parts, aerospace, and
sporting goods. The main drawback in some industries is the cost versus weigh
consideration. Titanium is considerably more expensive than steel or aluminum.
Manufacturers and fabricators must look at the benefits of saving on weight to
add strength while also minimizing expenses in some other areas.
Other industries Grade 2 has become primary metal include
oil and gas components, reaction and pressure vessels, tubing or piping
systems, heat exchangers, liners, flue-gas desulphurization systems and many
other industrial components. The fact that Grade 2 is commercially pure Titanium
and provides light weight and corrosion resistance but isn't quite as strong as
alloys like Grade 5 while still possessing excellent tensile strength, makes it
an ideal choice for high-pressure and temperature systems.
Titanium Grade 2 has good ductility or its ability to have
its shape changed, which allows for cold formability. Titanium can also be
easily machined, hot worked and welded. Hot working should be performed between
400°F and 600°F. Stress relieving should be performed by heating to a
temperature between 900°F and 1100°F followed by either forced air or slow
cooling. Welding of Grade 2 titanium can be performed using various methods
such as MIG and TIG. Inert gas shielding is crucial to prevent oxygen pickup
and embrittlement of the weld area. Preheat or post heat treatments are not
required.
Ultimately Grade 2 brings its skillset as pure alpha
titanium. It has become the most widely used titanium alloy in all product
forms for industrial service because of moderate strength and excellent
corrosion resistance and formability.