Grade 4 titanium is a type of unalloyed titanium that is highly corrosion-resistant and known for its excellent strength-to-weight ratio. It is commonly used in a variety of industries, including aerospace, automotive, and medical.
The key purposes of application in aerospace include weight saving, heat resistance, resistance to embrittlement at low temperature, high corrosion resistance and low-thermal expansion. An example of use is in the low fuel consumption aircraft manufactured by Airbus where it has grown to more than twice the amount used in conventional aircraft. Steel-based materials were used for portions where high strength was required (frames and joints) and have now been replaced by titanium to save weight and reduce the negative weight effects for fuel consumption.
Titanium has been mainly used for the fan and the compressor in the fore half sections for aircrafts, where the temperature is relatively low (600˚C or lower). Outside temperatures during flight can be −60˚C or lower which highlights the fact titanium is resistant to embrittlement at low temperatures. Furthermore, there is no concern about corrosion even when dew condenses after a drop in temperature. It is because of all these positive attributes that titanium proves to be a material appropriate for aircraft.
Beyond the aerospace industry one of the key advantages of grade 4 titanium is its ability to withstand harsh environments. It is particularly resistant to saltwater and other corrosive materials, making it a popular choice for applications in marine environments. Today it is frequently specified as first choice for offshore piping systems, heat exchangers, and a wide range of ancillary equipment for both water and product management in both critical and general applications.
This durability also makes it an excellent choice for medical implants and other medical devices, as it will not break down or corrode over time. Medical implants made from titanium routinely last 20 or more years inside the human body. It is stronger and lighter than stainless steel, which largely accounts for its widespread use in surgical implants. Because it isn't magnetic, medical titanium doesn't interfere with magnetic resonance imaging (MRI) machines. Because of this property, patients with titanium implants can still safely undergo MRI examinations. Unlike other metals, it can remain in constant contact with living tissue without adversely affecting it. Titanium implants have an engineered bio-interface that increases cell contact area by as much as 75%, enhancing the cell's binding properties which further reduces the chance of implant rejection. Medical titanium implants can physically bond with natural bone, eliminating the need for adhesives.
In addition to its corrosion resistance, grade 4 titanium is also known for its strength and lightweight nature. It is the strongest of the commercially pure grades, making it ideal for applications where strength is a key requirement. At the same time, its low density makes it much lighter than other metals, which is important in industries such as motorsports where weight is a critical factor.
Anecdotally, the conversion to more titanium parts in motorsports can be attributed to record setting runs in drag racing as well as major improvements in speed for NASCAR, Indy Car and sprint car racing. In some instances, weight reduction of four to seven pounds has been recognized simply by replacing aluminum or steel fasteners with titanium fasteners. Titanium has been used for frame supports, a-frames and wheelie bars to reduce weight and add strength.
Overall, grade 4 titanium is a versatile and durable material that is well-suited to a wide range of applications across many industries. Its corrosion resistance, strength, and lightweight nature make it a popular choice in a variety of industries, and its ability to withstand harsh environments makes it an excellent choice for use in challenging applications.