How Is The Colored Surface Of Gr4 Titanium Parts Formed?

Titanium colored surface is due to the oxidation of the surface to generate titanium dioxide, titanium dioxide oxide film of different thicknesses of the refractive light of different colors, so the formation of many different colors. General titanium coloring oxidation, divided into atmospheric method, anodic oxidation method, deposition method. Today we will introduce the most used anodic oxidation method.

Titanium anodic oxidation, titanium and its alloys are placed in the corresponding electrolyte (such as sulfuric acid, chromic acid, oxalic acid, etc.) as the anode, and electrolysis is carried out under specific conditions and the effect of the applied current. Anode of titanium or its alloy oxidation, the formation of a thin layer of titanium oxide on the surface, the thickness of 5 ~ 30 microns, hard anodic oxide film up to 25 ~ 150 microns. After anodic oxidation of titanium or its alloys, improve its hardness and wear resistance, up to 250 ~ 500 kg / mm2, good heat resistance, hard anodic oxidation film melting point of up to 2320K, excellent insulation, breakdown voltage of up to 2000V, enhanced corrosion resistance, in the ω = 0.03NaCl salt spray after thousands of hours of non-corrosion. Oxide film thin layer with a large number of microporous, can adsorb a variety of lubricants, suitable for the manufacture of engine cylinders or other wear parts; film microporous adsorption capacity can be colored into a variety of beautiful and colorful colors. Non-ferrous metals or their alloys (such as titanium, magnesium and its alloys, etc.) can be anodized, this method is widely used in machinery parts, aircraft and automobile parts, precision instruments and radio equipment, daily necessities and architectural decoration and other aspects. Generally speaking, the anode is titanium or titanium alloy as anode, the cathode is selected lead plate, the titanium and lead plate together in aqueous solution, which has sulfuric acid, oxalic acid, chromic acid, etc., electrolysis, so that the surface of the titanium and lead plate to form a kind of oxidized film.

Pure titanium products have a dense layer of oxidized film on the surface, which can be well adapted to a variety of environments at room temperature, so there is no need for spraying, pure titanium kettles have strong corrosion resistance. Facing the weak acid or alkali environment outdoors, pure titanium kettle can cope with freely, no matter river water or rain, rocks or vegetation, pure titanium kettle can be in direct contact with it without being corroded. As the whole body of the kettle is not painted, the kettle shows the unique gray color of pure titanium products, which can also be heated directly on the fire source to become a dazzling color. The titanium kettle's brilliant color of titanium metal is covered with a very thin layer of naturally occurring oxide film (titanium and oxide TiO2). This layer of film can also become titanium rust, because its surface forms a high refractive index of the transparent film, the film plays the role of a prism, so that the refraction of light absorbs different wavelengths of light, you can see the color, and, if the thickness of this layer of oxidized film is artificially adjusted to 8 ~ 10um, according to the different wavelengths, can be presented in thousands of similar colors. Because this film is a transparent film with high refractive index, it can show colorful colors.

Photocatalysts were first discovered by Japanese scientists, and their effect was confirmed by Japanese scholar Takao Guan as early as 1965. Subsequently, the University of Tokyo, Professor Hondo Kenichi and his disciple Fujishima Akira discovered in 1972 with light irradiation of titanium dioxide electrodes, which can lead to water electrolysis reaction "Hondo-Fujishima effect", a sensation. Over the past 30 years, a large number of technicians in this practical road, painstaking research, and finally a few years ago began to apply it to the car disinfection and antifouling and other fields.

Photocatalyst is a new type of catalyst with nano-scale titanium dioxide as the main material, which reacts under the irradiation of light. Photocatalyst has the power of decontamination and cleaning: it can not only be used to decompose the dirt in the water, repel the odor, but also can be sprayed on the interior and exterior walls of the building, so that it is resistant to dust and dirt adhesion for a long period of time, to maintain the state of the cluster of new. According to the development of technical personnel, the titanium dioxide in the absorption of ultraviolet light in the sun, the internal electron will be stimulated to produce a strong oxidizing ability, damage to the cell membrane of the cell, can trap and kill more than 99% of the air in the bacterial plankton. Moreover, it can transform organic substances and harmful gases into harmless water, carbon dioxide and salt through redox reaction, so as to achieve the effect of water purification and air purification.