Titanium is divided into "pure titanium" and "titanium alloy" two categories, in each country will have their own standards, such as ASTM in the United States and JIS in Japan, and TA in China.
There are many grades of titanium and titanium alloys, according to ASTM standards, a total of 39 grades, industrial pure titanium such as Gr1, Gr2, Gr3, Gr4, titanium alloys such as Gr7, Gr11, Gr5, Gr23, Gr12, Ti-5Al-2.5Sn, titanium alloys are usually manufactured for a variety of different uses.
Industrial pure titanium is graded according to the content of impurity elements, and the content of elements will affect the ductility and strength of pure titanium. For example, oxygen content will affect the strength of pure titanium. The oxygen content of Gr-2 is higher than that of Gr-1, so the strength is higher than that of Gr-1. Among the four pure titanium grades, Gr-1 has the best corrosion resistance, followed by Gr-2.
Grade 1 titanium is the first of four industrial grades of pure titanium. It is the softest and most malleable of the industrial pure titanium grades. It has maximum formability, excellent corrosion resistance and high impact toughness.
Because of its diverse availability and wide availability, Grade 2 titanium is known as the "workhorse" of the commercial pure titanium industry, and it has many similarities to Gr-1 grade titanium, but is slightly stronger. Both are equally resistant to corrosion. It has good weldability, strength, ductility and formability.
This grade is the least used commercial grade of pure titanium, but this does not make it any less valuable. Grade Gr-3 is stronger than Grade Gr-1 and Grade Gr-2, has similar ductility, and is only slightly formable, but it has higher mechanical properties than the first two.
Grade 4 is considered the strongest of the four commercial pure titanium. It is also known for excellent corrosion resistance, good formability and weldability.
Gr5 has good tensile properties at ambient temperatures and practical creep resistance at temperatures up to 300℃ (570℉). Excellent resistance to fatigue and crack growth. Like most titanium alloys, Gr5 has outstanding corrosion resistance in most natural environments and many industrial process environments.
