There are four grades of commercially pure titanium. Pure titanium ranges from grade 1, which has the highest corrosion resistance, formability, and lowest strength, to grade 4, which offers the highest strength and moderate formability.
Grade 1 titanium is the first of four commercially pure titanium grades. It is the softest and most ductile of these grades. It possesses the greatest formability, excellent corrosion resistance, and high impact toughness but it is the weakest of the four grades. Grade 1 is the material of choice for any application where ease of formability is required. It is most commonly used in chemical processing, architecture, automotive parts, and aeronautic structures.
Grade 2 is “commercially pure" titanium and provides lightweight and corrosion resistance. It is slightly stronger than grade 1. It is used frequently in areas that require welding because of its strong weldability properties. It has good strength, ductility, and formability. grade 2 titanium bar and sheet are the prime choice for many fields including the medical industry and the marine industry since it has strong corrosion resistance.
Grade 3 titanium finds its home primarily in aerospace and industrial applications since they require moderate strength, excellent corrosion resistance, and good weldability. It is stronger than grade 1 and grade 2, but it is less malleable than the other two grades. This grade is the least used of the commercially pure titanium grades. Industries such as marine, medical, and aerospace use grade 3 consistently, and it is also used in chemical processing since that area requires moderate strength and major corrosion resistance.
Grade 4 is recognized as the strongest of the four grades of commercially pure titanium. It is also known for its excellent corrosion resistance, good formability, and weldability. Though it is normally used in airframe components, heat exchangers, CPI equipment, and condenser tubing it has recently found a niche as a medical-grade titanium.
There are six additional titanium alloys with grade 5 being the most popular. grade 5, or Ti 6Al-4V, is titanium alloyed with 6% aluminum and 4% vanadium. The resultant alloy increases strength, as well as heat and corrosion resistance. Titanium Engineers produces titanium bars, seamless tubes, and titanium machined components in titanium grade 5. This alloy offers its high strength at a light weight, useful formability, and high corrosion resistance. Titanium grade 5 is the most used titanium worldwide and is the most used alloy in oilfields.