Titanium pipe is a new type of metal material that has completely replaced traditional iron pipes and steel pipes in some aspects. So, what enabled it to quickly spread and replace traditional pipes? Let's take a look now.
The advantages of titanium tubes are:
1. The specific strength of titanium pipes is high. The density of titanium alloys is generally around 4.5g/cm3, only 60% of that of steel. The strength of pure titanium is only close to that of ordinary steel, and some high-strength titanium alloys exceed the strength of many alloy structural steels. Therefore, the specific strength (strength/density) of titanium alloy is much higher than that of other metal structural materials, and it can produce components with high unit strength, good rigidity, and light weight. At present, titanium alloy is used for the engine components, framework, skin, fasteners, and landing gear of aircraft.
2. Titanium pipes have high thermal strength. The usage temperature is several degrees higher than aluminum alloy, and it can still maintain the required strength at medium temperatures. It can work for a long time at temperatures ranging from 450 to 500 ℃. These two types of titanium alloys still have high specific strength in the range of 150 ℃ to 500 ℃, while aluminum alloy has a significant decrease in specific strength at 150 ℃. The working temperature of titanium alloy can reach 500 ℃, while that of aluminum alloy is below 200 ℃.
3. Titanium tubes have good corrosion resistance. Titanium alloys work in humid atmospheres and seawater media, and their corrosion resistance is much better than stainless steel; Strong resistance to pitting, acid corrosion, and stress corrosion; It has excellent corrosion resistance to organic substances such as alkali, chloride, chlorine, nitric acid, sulfuric acid, etc. However, titanium has poor corrosion resistance to reducing oxygen and chromium salt media.
4. Titanium tubes have 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 ℃. Therefore, titanium alloy is also an important low-temperature structural material.
5. Titanium tubes have high chemical activity. Titanium has high chemical activity and produces strong chemical reactions with O, N, H, CO, CO2, water vapor, ammonia, etc. in the atmosphere. When the carbon content is greater than 0.2%, hard TiC will be formed in the titanium alloy; When the temperature is high, the interaction with N will also form a TiN hard surface layer; At temperatures above 600 ℃, titanium absorbs oxygen to form a hardened layer with high hardness; An increase in hydrogen content can also form a brittle layer. Titanium also has a high chemical affinity and is prone to adhesion with friction surfaces.
6. Titanium pipes have low thermal conductivity and elastic modulus. Titanium has a low thermal conductivity and elastic modulus. The elastic modulus of titanium alloy is about half of that of steel, so its rigidity is poor and it is prone to deformation. It is not suitable for making slender rods and thin-walled parts. During cutting, the rebound amount on the machined surface is large, about 2-3 times that of stainless steel, causing severe friction, adhesion, and adhesive wear on the back of the cutting tool.
