Titanium is a transition element with a silvery-white appearance. It lies in the d-block of the 4th group and 4th period with atomic number 22. Titanium is a naturally occurring metal most abundant in Earth’s crust, combined in rocks, sand, clay, and other soils. It is also present in plants, animals, natural waters, and some stars and meteorites.
Producing pure Titanium is extremely difficult because of its high reactivity towards Oxygen and Nitrogen at elevated temperatures. Thus, manufacturers use the Kroll process to use one of the alloys Titanium, Titanium dioxide, also known as rutile, to do so. Titanium dioxide manufacturers treat it with carbon and chlorine to yield Titanium tetrachloride, further fractionally distilled and then reduced to produce metallic Titanium.
Titanium is called a wonder metal for a fact that is unique and amazing, exceptionally light, lustrous, and strong. It has a strong tolerance towards high stress and extreme heat. It is durable and protects itself by forming its oxide, and it can burn itself into rainbow colors when it gets anodized.
Properties of Titanium
There is no limit to the chemical, physical, thermal and mechanical properties of Titanium. A few of them are listed below.
Ductility
Titanium is highly brittle and can be broken apart easily when cold. However, Titanium becomes malleable and ductile at higher temperatures, which means it can be beaten into thin sheets and wires.
Density
The density of Titanium is 4.50g/cm3. Pure Titanium is not very dense. However, it is twice denser than aluminium and about as half dense as iron. Even in its unalloyed form, it is as strong as steel.
Tensile Strength
The tensile strength of pure Titanium is 220 MPa. Pure Titanium is highly brittle. However, titanium alloys have very high tensile strength meaning that they have a high tolerance to stress.
Resistance to corrosion
Titanium is known as an excellent corrosion resistance element because of the formation of a passive oxide surface. It can protect itself from any kind of corrosion even after exposure to seawater for more than three years. Its corrosion resistance makes it extremely useful for parts of aircraft, spacecraft, and ships.
Solubility
Titanium is water-insoluble. The best solvents for Titanium are hydrofluoric acid and some other acids when fluoride ions have been added to them.
Compounds of Titanium
Titanium exhibits oxidation states of +2, +3, and +4. Thus, it forms titanium oxide (TiO), dititanium trioxide (Ti2O3), and titanium dioxide (TiO2). The fourth oxidation state of Titanium is highly stable.
The most important titanium compound is Titanium dioxide. It is a non-toxic white powder that is used as a pigment in paints and enamels. It naturally occurs in nature as minerals octahedrite, anatase, and rutile.
Uses of titanium dioxide for manufacturing industries
Titanium dioxide is produced in two main forms: the primary is pigment grade while the secondary is an ultrafine product. The pigment grade titanium has excellent light-scattering properties, making it ideal for high opacity and brightness applications. At the same time, the ultrafine nanomaterial product is used where ultraviolet light absorption, such as in cosmetics sunscreens, is needed.
Uses of Pigment grade titanium dioxide
- Paints: In printing industries, titanium dioxide provides durability, and hence it is perfect for ensuring the longevity of paints and coating surfaces.
- Plastic and Rubber: Titanium dioxide is highly non-brittle and hence, a perfect material to build plastics, adhesives, and rubbers.
- Food contact material: Its lesser reactivity and opacity to visible, ultraviolet light titanium dioxide protects foods, beverages, and supplements from degradation.
- Medical industries: Because of the high purity of pigment grade titanium, it is used in drug tablets and capsule coatings.
- Paper: Titanium is also used to coat paper to make it right and opaque.
Uses of Ultrafine grade titanium dioxide
- Cosmetic sunscreens: It works as an efficient UV light absorber. Hence, protecting skin from harmful sun rays.
- Automotive Industries: Titanium is used as a support material for catalytic applications. It removes harmful exhaust emissions and nitrous oxide in automobile industries.
Biological Significance of Titanium
There is a reason why Titanium is called the wonder metal. The list of benefits that Titanium provides in biology is long and impressive. In addition, since it is physiologically inert, our human body cannot reject it. So, it is highly used in orthopedic and dental implants.
Titanium is extremely strong and lightweight; hence, it can be used almost anywhere in the body. This wonder metal is used in maxio-facial, dental, spinal, and orthopedic implants, bone screws for every joint in surgical instruments, and image-guided surgery. If used in implantation, it has done its job well for many years.
The modulus of elasticity of Titanium is significantly less, allowing it to mimic the modulus of bone. Therefore, the skeletal load is evenly distributed between the bone and implant, leading to a reduced incidence of degradation from stress. In addition, as Titanium is non-ferromagnetic, its effectiveness and longevity in the implant can be tracked through MRI.