(1) High strength. The density of titanium alloy is generally about 4.5g/cm3, which is only 60% of steel. The strength of pure titanium is close to that of ordinary steel. Some high-strength titanium alloys exceed the strength of many alloy structural steels. Therefore, the specific strength (strength/density) of titanium alloy is much greater than that of other metal structural materials. See Table 7-1, which can produce parts and components with high unit strength, good rigidity, and light weight. At present, titanium alloys are used in aircraft engine components, skeletons, skins, fasteners, and landing gear.
(2) High thermal intensity. The service temperature is several hundred degrees higher than that of aluminum alloy. It can still maintain the required strength at medium temperature. It can work for a long time at a temperature of 450~500℃. These two types of titanium alloys are still very high in the range of 150℃~500℃. Specific strength, while the specific strength of aluminum alloy decreases significantly at 150°C. The working temperature of titanium alloy can reach 500℃, while that of aluminum alloy is below 200℃.
(3) Good corrosion resistance. Titanium alloy works in moist atmosphere and sea water medium, its corrosion resistance is far better than stainless steel; it is particularly resistant to pitting corrosion, acid corrosion, and stress corrosion; it is resistant to alkali, chloride, chlorine organic substances, nitric acid, sulfuric acid It has excellent corrosion resistance. However, titanium has poor corrosion resistance to reducing oxygen and chromium salt media.
(4) Good low temperature performance. Titanium alloys can still maintain their mechanical properties at low and ultra-low temperatures. Titanium alloys with good low temperature performance and extremely low interstitial elements, such as TA7, can maintain a certain degree of plasticity at -253°C. Therefore, titanium alloy is also an important low-temperature structural material.
(5) High chemical activity. Titanium has high chemical activity, and produces a strong chemical reaction with O, N, H, CO, CO2, water vapor, ammonia, etc. in the atmosphere. When the carbon content is more than 0.2%, it will form hard TiC in the titanium alloy; when the temperature is higher, it will also form a hard surface layer of TiN when it interacts with N; when the temperature is above 600℃, titanium absorbs oxygen to form a hardened layer with high hardness ; When the hydrogen content increases, an embrittlement layer will also be formed. The depth of the hard and brittle surface layer produced by absorbing gas can reach 0.1-0.15 mm, and the degree of hardening is 20%-30%. Titanium also has a high chemical affinity and is easy to adhere to the friction surface.
(6) The thermal conductivity is small, and the elastic modulus is small. The thermal conductivity of titanium λ=15.24W/(m.K) is about 1/4 of nickel, 1/5 of iron, and 1/14 of aluminum. The thermal conductivity of various titanium alloys is about 50% lower than that of titanium. The modulus of elasticity of titanium alloy is about 1/2 of that of steel, so its rigidity is poor and easy to deform. It is not suitable to make slender rods and thin-walled parts. The springback of the machined surface during cutting is very large, about 2~3 of stainless steel. Times, causing severe friction, adhesion, and adhesive wear on the flank of the tool. Alloying of Titanium Titanium alloy is an alloy composed of titanium as the base and adding other elements. Titanium has two isomorphs: close-packed hexagonal α titanium below 882°C, and body-centered cubic β titanium above 882°C.
ASTM B265 TA6V Titanium Plate Titanium Rotary Sputtering Target Ti 15333 Titanium Strip Ti 7-4 Titanium Bar
ASTM B265 TA6V Titanium Plate Titanium Rotary Sputtering Target Ti 15333 Titanium Strip Ti 7-4 Titanium Bar
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