Titanium alloy is a new important structural material used in the aerospace
industry, the specific gravity, strength and temperature of use are between
aluminum and steel, but higher than strength and excellent resistance to
seawater corrosion and ultra-low temperature performance.
In 1950, the United States for the first time in the F-84 fighter bomber
used as the rear fuselage heat shield, air guide hood, tail cover and other
non-force components. The use of titanium alloy began in the 60's from the rear
fuselage to the middle fuselage, partially replacing structural steel
manufacturing spacers, beams, flap rails and other important supporting
components.
The amount of titanium alloy used in military aircraft increased rapidly,
reaching 20% to 25% of the weight of aircraft structure. Since the 1970s,
civilian aircraft began to use a large number of titanium alloy, such as Boeing
747 aircraft with titanium volume of more than 3640 kg. Aircraft with mach less
than 2.5 use titanium primarily to replace steel to reduce structural
weight.
When the thrust ratio of the aviation engine is raised from 4 to 6 to 8 to
10, and the outlet temperature of the compressor is correspondingly increased
from 200 to 300 degrees C to 500 to 600 degrees C, the original low-pressure
compressor discs and blades made of aluminum must be replaced with titanium
alloy, or titanium alloy instead of stainless steel to make high-pressure
compressor discs and blades to reduce structural weight.
In the 1970s, the amount of titanium alloy in aviation engines generally
accounted for 20% to 30% of the total weight of the structure, mainly used in
the manufacture of compressor components, spacecraft mainly use titanium alloy
high-ratio strength, corrosion and low temperature resistance to create a
variety of pressure vessels, fuel tanks, fasteners, instrument straps, frames
and rocket shells.