Original title: Introduction to several common applications of titanium alloy
materials such as titanium rod and titanium anode Introduction of several common
applications of titanium alloy materials such as titanium rod and titanium anode
Titanium and titanium anodes have good welding, cold and hot pressure processing
and mechanical processing performance, can be processed into a variety of
profiles, plates and pipe supply. Titanium is an ideal structural material. The
density of titanium is only 4.5 G/m3, which is 43% lighter than steel, but the
strength of titanium is twice that of iron and almost five times that of pure
aluminium. Has low density and high strength performance. This combination of
high strength and low density gives titanium a very important place in
technology. At the same time, the corrosion resistance of titanium is close to
or better than that of stainless steel, so it has been widely used in petroleum,
chemical industry, pesticides, dyes, paper making, light industry, aviation,
space development, marine engineering and so on. Titanium alloys have high
specific strength (the ratio of strength to density). Titanium alloys have
played an irreplaceable role in aviation, military industry, shipbuilding,
chemical industry, metallurgy, machinery, medical and other fields. For example,
after heat treatment, the strength limit of the alloy composed of titanium,
aluminum, chromium, vanadium, molybdenum, manganese and other elements can reach
1176.8-1471 MPa, and the specific strength can reach 27-33. The specific
strength of the alloy steel with the same strength is only 15.5-19. Titanium
alloys are widely used in shipbuilding, chemical machinery and medical equipment
because of their high strength and corrosion resistance. Among them,
corrosion-resistant titanium alloy is mainly used in reactors, towers,
autoclaves, heat exchangers, pumps, valves, centrifuges, pipelines, pipe
fittings, electrolyzers and so on in various strong corrosive environments.
However,
titanium
filler rod, the application of titanium and its alloys is limited due to
their high price. Expand the full text (1) Titanium by iodine method, grade TAD
It is high-purity titanium obtained by iodination method, so it is called
iodination titanium, or chemically pure titanium. However, it still contains
interstitial impurities such as oxygen, nitrogen and carbon, which have a great
influence on the mechanical properties of pure titanium. As the purity of
titanium increases, the strength and hardness of titanium decrease
significantly; therefore, it is characterized by good chemical stability, but
very low strength. Because of its low strength, high purity titanium is of
little interest as a structural material and is rarely used in industry. At
present, industrial pure titanium and titanium alloys are widely used in
industry. (2) Commercially pure titanium Unlike chemically pure titanium,
industrially pure titanium contains more oxygen, nitrogen,
titanium
plate gr7, carbon and many other impurity elements (such as iron, silicon,
etc.). It is essentially a titanium alloy with low alloy content. Compared with
chemically pure titanium, its strength is greatly improved because it contains
more impurity elements, and its mechanical and chemical properties are similar
to those of stainless steel (but its strength is still lower than that of
titanium alloy). The characteristics of industrial pure titanium are: low
strength, good plasticity, easy processing, stamping, welding, good
machinability; good corrosion resistance in the atmosphere, sea water, wet
chlorine and oxidizing, neutral, weak reducing medium, oxidation resistance is
superior to most austenitic stainless steel; but poor heat resistance, the use
temperature should not be too high. Commercially pure titanium is divided into
three grades of TA 1, TA 2 and TA 3 according to its impurity content. The
interstitial impurity elements of the three kinds of commercial pure titanium
increase gradually, so the mechanical strength and hardness also increase
gradually, but the plasticity and toughness decrease correspondingly.
Commercially pure titanium TA2 is commonly used in industry because of its
moderate corrosion resistance and comprehensive mechanical properties. TA3 can
be selected when the requirements for wear resistance and strength are high. TA1
can be selected when good formability is required. Industrial pure titanium is
mainly used for stamping parts and corrosion-resistant structural parts with
working temperature below 350 ℃, low stress and good plasticity, such as
aircraft framework, skin, engine accessories, seawater corrosion-resistant
pipelines, valves, pumps, hydrofoils and seawater desalination system parts for
ships; Chemical heat exchangers, pumps,
titanium bar
gr7 ,
titanium
bar grade 5, distillation towers, coolers, agitators, tees, impellers,
fasteners, ion pumps, compressor valves and diesel engine pistons, connecting
rods, leaf springs, etc. (3) Alpha titanium alloy, TA4, TA5, TA6, TA7. This kind
of alloy is in α-type single-phase state at room temperature and service
temperature, and can not be strengthened by heat treatment (annealing is the
only form of heat treatment), mainly relying on solid solution strengthening.
The strength at room temperature is generally lower than that of β and α + β
titanium alloys (but higher than that of commercial pure titanium), while the
strength and creep strength at high temperature (500-600 ℃) are the highest
among the three types of titanium alloys; and the microstructure is stable, the
oxidation resistance and weldability are good, the corrosion resistance and
machinability are also good, but the plasticity is low (the thermoplasticity is
still good), and the stamping performance at room temperature is poor. Among
them, TA7 is the most widely used, which has high strength and sufficient
plasticity in the annealed state, good weldability, and can be used below 500 ℃;
when the content of interstitial impurity elements (oxygen, hydrogen, nitrogen,
etc.) Is extremely low, it also has good toughness and comprehensive mechanical
properties at ultralow temperature, and is one of the excellent ultralow
temperature alloys. The tensile strength of TA4 is slightly higher than that of
commercial pure titanium, and it can be used as a structural material in the
medium strength range. It is mainly used as welding wire in China. TA5 and TA6
are used for parts and weldments working in corrosive medium below 400 ℃, such
as aircraft skin, skeleton parts, compressor shell, blades, ship parts, etc. TA7
is used for structural parts and various molded parts working below 500 ℃ for a
long time, and can be used up to 900 ℃ for a short time. It can also be used for
ultra-low temperature (-253 ℃) parts (such as containers for ultra-low
temperature). (4) Beta titanium alloy, grade TB2. The main alloying elements of
this kind of alloy are β phase stabilizing elements such as molybdenum, chromium
and vanadium, which can easily retain the high temperature β phase to room
temperature during normalizing and quenching to obtain a more stable β phase
structure, so it is called β type titanium alloy. β-type titanium alloy can be
strengthened by heat treatment, and has high strength, good welding performance
and pressure processing performance; but the performance is not stable enough,
and the melting process is complex, so its application is not as wide as α-type
and α + β-type titanium alloy. It can be used for parts working below 350 ℃, and
is mainly used for manufacturing various sheet stamping parts and welding parts
with integral heat treatment (solid solution and aging), such as compressor
blades, wheel disks, shafts and other heavy load rotating parts, as well as
aircraft components. TB2 alloy is generally delivered under solution treatment
and used after solution treatment and aging. (5) TC6, TC9 and TC10 commonly used
for α + β titanium rods and titanium alloys This kind of alloy has α + β
two-phase structure at room temperature, so it is named α + β titanium alloy. It
has good comprehensive mechanical properties, most of which can be strengthened
by heat treatment (but TC1, TC2 and TC7 can not be strengthened by heat
treatment), good forging, stamping and welding properties, machinability, high
room temperature strength and high heat resistance below 150-500 deg C. Some of
them (such as TC1, TC2, TC3, TC4) also have good low temperature toughness and
good resistance to seawater stress corrosion and hot salt stress corrosion, but
the disadvantage is that the structure is not stable enough. Among these alloys,
TC4 is the most widely used, accounting for about half of the production of
existing titanium alloys. The alloy not only has good mechanical properties at
room temperature, high temperature and low temperature, but also has excellent
corrosion resistance in a variety of media, and can be welded, cold and hot
formed, and can be strengthened by heat treatment; therefore, the alloy is
widely used in aerospace, ships, chemical industry and other industrial
departments. TC1 and TC2 can be used for stamping parts, welding parts, die
forgings and various parts processed by bending below 400 ℃. These two alloys
can also be used as low temperature structural materials. TC3 and TC4 can be
used as parts for long-term operation below 400 ℃, structural modules, various
containers, pumps, low-temperature components, ship pressure shells, tank
tracks, etc. The strength is higher than that of TC1 and TC2. TC6 can be used
below 400 ℃ and is mainly used as a structural material for aircraft engines.
TC9 can be used to manufacture parts working below 560 ℃ for a long time, mainly
used in compressor disks and blades of aircraft jet engines. TC10 can be used to
manufacture parts working below 450 ℃ for a long time, such as aircraft
structural parts, landing gear, honeycomb connection components,
titanium
exhaust tubing, missile engine shells, weapon structural parts, etc. Return
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