About the Properties of Titanium and Titanium Alloys

As a new type of material, titanium alloy has completely replaced steel or iron in many aspects, such as aerospace, petroleum processing and automobile manufacturing. The main reason for this is that titanium and titanium alloys have very good physical and chemical properties. Next, several typical features will be introduced:

1. High strength and thermal strength

The density of titanium alloy is generally around 4.5g/cm3, which is only 60% of that of steel. The operating temperature is higher than that of aluminum alloy, and the required strength can still be maintained at medium temperature, and it can work stably for a long time at a temperature of 450℃-500℃. Some high-strength titanium alloys have surpassed the strength of many alloy structural steels, and can point to components with high unit strength, good rigidity, and light weight. Currently widely used in aircraft engine parts, frames, fasteners and landing gear.

2. High chemical activity

Titanium reacts strongly with gases such as oxygen, carbon dioxide, water vapor and ammonia 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, a hard surface layer of TiN will also be formed when it interacts with N; when the temperature is above 600 ℃, titanium absorbs oxygen to form a hardening with high hardness Floor. So its strength, hardness and corrosion resistance are better.

3. Strong low temperature performance

Low-temperature titanium alloys represented by titanium alloys TA7 (Ti-5Al-2.5Sn), TC4 (Ti-6Al-4V) and Ti-2.5Zr-1.5Mo, etc., their strength increases with the decrease of temperature, but the plasticity does not change. big. It maintains good ductility and toughness at a low temperature of -196-253 °C, and avoids the cold brittleness of metals. It is an ideal material for low-temperature containers, storage tanks and other equipment.

4. Strong bio-affinity

Two titanium alloys, Ti6Al7Nb and Ti13Nb13Zr, are often used in the medical field as raw materials for surgical implants. Their elastic modulus is very close to that of human bone, and they are also non-toxic and non-magnetic. It can be used by the human body for a long time to help people in better medical recovery.