Pure Titanium
Pure titanium generally refers to titanium materials whose purity (mass fraction) is greater than 99%, and the purity of high purity titanium can reach the 4N level (99.99%) or even higher. As a member of titanium series products, high purity titanium has low density, high melting point, strong corrosion-resistance, and other properties, but also has low strength, good plasticity (elongation can reach 50% ~ 60%, section shrinkage can reach 70% ~ 80%) and other characteristics. In recent years, with the rapid development of aerospace, electronic information, and other high-tech industries, the amount of high purity titanium is more and more, using appropriate methods to manufacture high-quality, low-cost high purity titanium, related to the development of these industries.
High purity titanium is used as a control electrode, diffusion barrier layer, and wiring material in the form of TiSix, TiN, and W-Ti in semiconductor very large-scale integrated circuits. And the high-quality high purity titanium powder is used to manufacture the net formed titanium powder metallurgy compact parts and porous parts, such as the use of titanium and titanium alloy good corrosion resistance and high specific strength, used to manufacture aircraft automobile engine components and petroleum and chemical industry and other wear-resistant parts. With the rapid development of science and technology and industrial application, it is urgent and necessary to increase the research on the preparation technology of high purity titanium and its powder.
Preparation Method
(1) Electrolytic high-pressure torsion superfine crystallization processing of titanium material: High-purity titanium is chosen as the raw material and subjected to molten salt electrolysis at room temperature or a temperature below 0.4 times the melting point. The specimen is molded into a disk shape and subjected to several gigapascals of pressure. Meanwhile, the lower die rotates, exerting axial compression and tangential shear deformation through friction.
(2) Hydrogenation treatment of ultra-fine crystal titanium: After high-pressure torsion, the raw titanium is placed in a vacuum furnace. The furnace is evacuated, and then argon is introduced as a protective gas to eliminate residual oxygen. The raw material is preheated and activated through a heating and insulation process at varying temperatures. Hydrogen is introduced into the furnace to maintain a slightly positive pressure atmosphere. The raw titanium absorbs hydrogen, and after a certain period, it is cooled and milled to remove titanium hydride.
(3) Removal of titanium hydride through ball milling refinement: The titanium hydride powder is ground using a planetary ball mill in an argon atmosphere. The dehydrogenation of the powder occurs in a vacuum furnace. After a specific period of dehydrogenation, the titanium undergoes further grinding and breaking to produce ultrafine high-purity titanium powder.
