（1）Titanium alloy has high strength and small specific gravity, so its specific strength is high. The specific strength of commonly used (α+β) titanium alloy is 23-27, while the specific strength of alloy steel is 16-20, so parts with high strength, good rigidity and light weight can be manufactured.

（2）Titanium alloy has good thermal stability and high strength at high temperature. Its strength is about 10 times higher than aluminum alloy at 300~500℃. Therefore, it is commonly used as a zero-component for long-term use at 350℃.

（3）Good corrosion resistance. Due to the dense and hard oxide film formed on the surface of titanium alloy, its corrosion resistance is better than stainless steel. It has superior corrosion resistance to alkali, chloride, nitric acid, sulfuric acid, etc.

（4）High chemical activity. At a certain temperature, titanium can produce a strong chemical reaction with oxygen, nitrogen, hydrogen, carbon monoxide, 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 the temperature is higher than 600°C, titanium will absorb oxygen and form a hardened layer with high hardness. In addition, when the hydrogen content increases, a catalytic layer is formed. This kind of hardened layer, which grows by absorbing gas, has a depth of 0.1 to 0.15 mm, and its hardening degree is 20 to 30%.

（5）Low thermal conductivity. The thermal conductivity of industrial pure titanium is 16.3W/m·K, which is about 1/4 of nickel, 1/5 of iron, and 1/10 of aluminum. Titanium alloys have lower thermal conductivity. At 20°C, the thermal conductivity of 45 steel is 50.24W/m·K.

（6）The modulus of elasticity is low. The elastic modulus of industrial pure titanium is 0.108x106MPa, which is about 1/2 of that of steel. At a temperature of 20°C, the elastic modulus of 45 steel is 0.207x106MPa. Due to the low modulus of elasticity, the thin-walled parts and the elongated shaft are easily deformed under the action of the grinding force.