Advantages of titanium plate

Titanium tube is a highly active metal, and its activity increases with increasing temperature.

Titanium tubes and their alloys will interact with oxygen when heated in air or an oxygen-containing atmosphere. When heated below 428℃, a protective oxide film is formed. When the temperature rises, the thickness of the oxide film increases. When the temperature is above 538℃, the oxide film begins to lose its protective effect. Oxygen diffuses through the film into the metal, forming obvious gas infiltration. Floor. If it rises above 815°C, a loose oxide scale will form on the surface of the titanium alloy.

In order to prevent the titanium alloy from oxidizing, absorbing hydrogen, and other trace element pollution during superplastic forming, technical measures need to be taken to make the formed titanium alloy parts have excellent properties.

At present, the main measures are coating protection, vacuum heating, and inert gas (argon) protection.

1. Coating protection law

After cleaning, the surface of the formed blank is coated with a protective coating of a certain thickness. After the part is de-molded, the coating is removed by alkaline washing, acid washing, or sand blowing.

The coating should have the following main properties:

a. High temperature resistance, can be used under high temperature of 750-1050℃;

b. It should have a certain lubricating effect to prevent the blank from being scratched during forming;

c. The coating can be firmly attached to the surface of the blank under the working temperature;

d. Easy to remove after heating;

e. No harmful substances, no pollution to the environment and harm to human health.

The coatings that have been identified as suitable for superplastic forming of titanium tubes and titanium alloys are: Ti-2 alcohol-soluble preparations can be used in conjunction with Ti-3 graphite lubricants, suitable for hot forming at 750-1050°C; KBC-12 Water-soluble preparation, can be used in conjunction with graphite water agent.

2. Vacuum forming

For titanium pipes, vacuum forming is the most ideal for β-type titanium alloys with thinner parts, higher requirements for surface brightness, and stronger sensitivity to hydrogen embrittlement.

Vacuum forming does not necessarily require expensive vacuum heating equipment. As long as a sealed space is created between the blank and the upper and lower cavities of the mold, the air in the upper and lower cavities is gradually extracted by a vacuum unit during the heating process, especially when the temperature is above 400℃ to the forming temperature, the temperature of the upper and lower cavities of the mold When the vacuum degree is above 10^(-3) Torr, the valve of the pipeline is changed during forming, and the forming purpose is achieved by filling with argon gas. This method is used in the forming of the titanium foil corrugated board, and satisfactory results are obtained. When the vacuum degree is controlled at 10^(-3) Torr, the hydrogen content is lower than the standard requirement. When the vacuum degree reaches 10^(-5) Torr, a bright surface part can be obtained.

In addition, for parts with medium thickness and no higher requirements for surface and concave brightness, vacuum argon protection can also be used to test this aspect in the formation of spherical gas cylinders, and the effect is also good.
Gr1 Pure Titanium Plate      Gr23 Ti-6Al-4V ELI Titanium Pipe      F2 Pure Titanium Forging      F9 Titanium Forging