TA18 titanium alloy tube Ti-3Al-2.5V titanium alloy tube

TA18 titanium alloy composition for Ti-3Al-2.5V, from the TC4 (Ti-6Al-4V) titanium alloy evolved from a near-alpha-type titanium alloy, is developed as a cold machinable tubing applications.TA18 titanium alloy has a good room temperature, high temperature mechanical properties and corrosion resistance, but also has excellent hot and cold machining process plasticity, molding, welding performance and corrosion resistance. It also has excellent plasticity, formability, weldability and corrosion resistance in hot and cold working processes. At room temperature and high temperature its strength is 20%-50% higher than pure titanium, welding performance and cold forming performance is better than TC4 alloy.

TA18 alloy is generally used in the annealed state, but also in the cold working and de-stressed annealed state, can also be used in the manufacture of working temperature up to 315 ℃, and a certain degree of strength and oxidation resistance requirements of the components, such as TA18 titanium alloy seamless tube in the aerospace industry is suitable for use in aircraft and engine high-pressure-resistant, lightweight hydraulic and fuel and other piping systems.

TA18 titanium alloy tube surface finishing process: TA18 in the electrolytic-magnetic composite grinding process, due to wear-assisted passivation and passivation-assisted wear of the synergistic effect, so in a reasonable process conditions, its surface burrs, scratches and other defects can be effectively removed, is conducive to the improvement of its surface micro-morphology, to obtain good surface quality. When the magnetic grinding particles with a particle size of 185 μm were used to grind the inner surface of TA18 tubes for 50 min at an electrolytic voltage of 9 V, the grinding effect was the best, the surface of the workpiece was uniform and flat, and the surface roughness Ra was reduced from the original 1.60 μm to 0.13 μm.

Cold rolling process of TA18 titanium alloy: (1) With the increase of the feeding volume, the radial tensile strain and circumferential compressive strain in the open area will increase, and the forming load will increase, resulting in the reduction of mold life. When the feeding amount is too large, it will also cause the metal to overflow the roll seam, resulting in cracking or folding. (2) Rolling speed increases, radial tensile strain and circumferential compressive strain are reduced, the vertical component force is also reduced. (3) The friction coefficient increases, the radial tensile strain and annular compressive strain in the open area decreases, and the forming load increases. For thick-walled tubes that are prone to internal surface quality problems, it is recommended that friction be increased appropriately.