How to reduce the manufacturing and processing costs of industrial pure titanium

Titanium and titanium alloys have broad application prospects in the military, civil and other fields due to their low density, high specific strength, high flexural strength ratio, good plastic toughness, good corrosion resistance, etc. Their performance and the level of manufacturing technology have a direct impact on the development of these fields and the level of improvement. The bottleneck in expanding the titanium alloy market is that titanium extraction, melting and machining are difficult, which leads to high production costs. The production cost of titanium ingot is about 30 times that of the same weight steel ingot, 6 times that of aluminum ingot, of which the cost of titanium sponge production from ore to magnesium reduction is about 20 times that of the production of the same weight iron. At present, the cost of each ton of industrial pure titanium is about 7.5 ~ 10 $ / kg, while the production cost of aerospace titanium alloy is as high as 40 $ / kg .

Therefore, cost reduction is mainly to reduce the cost of industrial pure titanium production and titanium and titanium alloy manufacturing and processing costs. In order to reduce the cost of titanium alloys, foreign countries vigorously develop titanium alloys without cutting, less cutting near-net shape process, powder metallurgy technology is one of the near-net shape process. Manufacture of titanium alloy parts currently there are three main methods: ① traditional forging material processing; ② casting; ⑧ powder metallurgy. Material processing with forging, its material properties are excellent, but waste, processing, high cost, and difficult to obtain the shape of complex products; casting can be obtained in the shape of complex net shape or near-net shape of the product, the cost is lower, but the casting process of the material composition segregation, loosening, shrinkage of solenoids and other defects are difficult to avoid, the material performance is low. The powder metallurgy technology of titanium alloy overcomes the shortcomings of these two methods, and at the same time has their advantages. Therefore, domestic and foreign researchers have carried out a lot of work on the preparation of titanium alloy by powder metallurgy technology. In this paper, several kinds of powder metallurgy technologies for the preparation of high-performance titanium alloys and their applications have been researched and developed abroad in recent years, and their applications are briefly introduced.1 New powder metallurgy preparation technology 1.1 Metal injection molding (MlM)

Metal powder injection molding (MIM) technology, as a near-net forming technology, can prepare high-quality, high-precision complex parts, which is considered to be one of the most advantageous forming technologies. Manufacturing titanium and titanium alloy near-net shape parts by MIM method can significantly reduce the processing cost. It is estimated that the current production volume of titanium MIM parts around the world is 3-5t per month. with the improvement of the process of preparing titanium powder and the reduction of powder cost -, the production volume of titanium alloy injection molding parts is on a growing trend. Japan's first MIM technology to produce Ti a 4wt% Fe alloy sports cleats. Now the largest titanium powder injection molding production plant is Japan Injex, monthly production of about 2 ~ 3 t. Titanium MIM products have been in the golf head, automobile, medical equipment, dental implants and watch cases and straps and other aspects of the application. Titanium alloy case made by Hitachi metal Precision Company and Casio Computer Company in Japan won the MIM Award of Merit at the International Powder Metallurgy Conference in 1999, and this watch can still operate normally at a water depth of 200m. Some Japanese universities use Sumitomo Sitix aerosolized spherical titanium powder, by the MIM method to obtain a Ti 6Al 4V, Ti 12Mo, Ti 5Co alloy. Material properties are better than the same conditions under the same conditions with conventional powder metallurgy process produced by the material properties, fully reached the same composition of the melting and forging material level. In addition, a Japanese company used injection molding method to manufacture titanium-iron alloy parts with complex shapes, such as the sole nails of track and field running shoes. The method will be titanium-iron alloy (Ti a 5wt% Fe) powder and organic binder mix, injection molding at 196MPa pressure, in 550 degrees degreasing, and then in the 1000-1400 degrees, 1.33 × 1O Pa conditions for vacuum sintering. Compared with molybdenum alloy spikes, the titanium-iron alloy spikes made in this way have improved wear resistance and impact resistance. And the weight is reduced by 45%.