Titanium alloy in addition to high strength, good corrosion resistance, any other characteristics?
Feb 24, 2017
Titanium alloy corrosion resistance is excellent, the density is small, fatigue strength and crack propagation ability, in the aviation, aerospace, automotive, shipbuilding, energy and other industries have a wide range of applications. Titanium excellent corrosion resistance and good specific strength, the titanium tube than other traditional metal pipe fittings made of thinner products, better heat transfer effect.
Titanium alloy is currently one of the most widely used titanium alloy, its high strength, good corrosion resistance, but at home and abroad seamless titanium tube market is difficult to see TC4 seamless steel tube. TC4 titanium mainly to the main plate, the market pipe to hot extrusion or oblique perforation and other methods of production of high-strength thick-walled tube-based.
The main reason for this present situation is the high strength of titanium alloy, cold rolling forming difficult. In order to solve the key technology of seamless tube cold forming, the school and enterprise carried out a series of research. Such as the use of direct cold-rolled forming process to produce high-strength titanium alloy pipe, not only greatly reduce production costs, while the titanium alloy to meet the requirements of high-performance applications.
The billets were rolled into a pipe with a total deformation of 70% by two passes and three passes. The temperature was 800 ℃ × 1h vacuum annealing, the cooling method for the furnace cooled to 500 ℃ after air cooling to room temperature, observed its organizational performance changes. The conclusion is:
In the case of small deformation volume billet, the wall thickness deviation is small, the surface roughness gradually decreases; large deformation billet, wall thickness deviation, will affect the follow-up road rolling pipe thickness deviation. The total amount of deformation of the same circumstances, the more rolling, pipe elongation, the greater the hardness, the higher the strength.
The large-scale deformation of the flow of material when the material was strip-like, small deformation of the rolling material flow was beam, in the road between the heat treatment conditions and the subsequent rolling process of the same circumstances, large deformation The shrinkage of the pipe tissue is more serious. The anisotropy of small deformation is not significant; the anisotropy of mechanical properties in multi-pass rolling has some fluctuation.