When the hydrogen content in the titanium exhaust tube is too much, the impact toughness and notch tensile strength will drop sharply due to brittleness, so it is generally prescribed that the hydrogen content in the titanium threaded tube should not exceed 0.015%. In order to reduce the amount of hydrogen absorption, the parts should remove fingerprints, rolling mill marks, grease, and other residues before heat treatment. There is no moisture in the atmosphere of the heat treatment furnace. If the hydrogen content of the Gr23 Titanium Tube exceeds the allowable value, it must be removed by vacuum annealing. Vacuum annealing for dehydrogenation is generally maintained at 538-760 ° C and pressure below 0.066 Pa for 2-4 hours.
When the temperature does not exceed 540 ℃, the oxide film on the surface of the titanium tube will not be significantly thickened, and at a higher heat treatment temperature (above 760 ℃), the oxidation rate will rapidly accelerate, and at the same time, oxygen will expand into the material to form a diffusion layer— Pollution layer. The oxygen contaminated layer has a high brittleness ratio and causes cracks and damage on the part surface. There are mechanical processing methods (such as sandblasting, house cutting, etc.) or chemical methods such as pickling and chemical milling to remove the contaminated layer of oxygen. During the heat treatment, the heating time should be as short as possible on the premise of ensuring the heat treatment of the meteorite. It is performed in a vacuum furnace or a heating furnace of inert gas (argon, nitrogen, etc.). The appropriate application can also avoid or reduce the pollution generated by the titanium tube parts when they are heated in the air furnace.
When the temperature does not exceed 540 ℃, the oxide film on the surface of the titanium tube will not be significantly thickened, and at a higher heat treatment temperature (above 760 ℃), the oxidation rate will rapidly accelerate, and at the same time, oxygen will expand into the material to form a diffusion layer— Pollution layer. The oxygen contaminated layer has a high brittleness ratio and causes cracks and damage on the part surface. There are mechanical processing methods (such as sandblasting, house cutting, etc.) or chemical methods such as pickling and chemical milling to remove the contaminated layer of oxygen. During the heat treatment, the heating time should be as short as possible on the premise of ensuring the heat treatment of the meteorite. It is performed in a vacuum furnace or a heating furnace of inert gas (argon, nitrogen, etc.). The appropriate application can also avoid or reduce the pollution generated by the titanium tube parts when they are heated in the air furnace.