Titanium plate metallurgy skills suitable for the automotive industry
GR1 GR2 GR3 GR4 titanium sheet has the characteristics of low density, high specific strength and corrosion resistance, and has great application potential in the automotive industry. The use of titanium and titanium alloys in cars can save fuel, reduce engine noise and vibration, and improve life expectancy. However, for a long time, automotive materials have been dominated by steel, Al and other materials. In order to enter the automotive market, in addition to its own functional advantages, the cost must be further reduced to a level acceptable to the automotive industry. Ti titanium plate metallurgical parts for automobiles is a field with a long-term prospect, but currently restricted by factors such as cost, the application promotion is developing slowly. The use of leading titanium plate metallurgy technology to prepare Ti titanium plate metallurgical parts can not only greatly reduce the cost, but also help the promotion of Ti and its alloys in the automotive industry, making it another big application after the aerospace industry category. The development of low-cost titanium and its alloy titanium plates can provide low-cost raw materials for titanium-titanium plate metallurgical parts for automobiles. From existing technology, be suitable for the car industry to mainly contain sponge body powder method, hydrodehydrogenation method and metal hydride restoration method that are used in automobile industry.
1、 Sponge powder method. This is currently a method that can meet the needs of the automobile industry for titanium plates in terms of cost. It mainly uses the traditional sponge body and the residual materials in the process to crush it; the obtained titanium plates are often thicker and richer. Cl element. Huachang Company of the United States uses the gas phase method to continuously introduce TiCl4 and Mg vapor into a tubular furnace at 850 ° C to quickly generate fine Ti powder and MgCl2, but it is difficult to separate such fine powder from MgCl2 and has a high O content; Japan invented a Spray reaction method, the gas is sprayed onto the liquid Mg to make it react to form particles. The test shows that for every 100 grams of Mg and 400 grams of TiCl4, about 100 grams of Ti powder with a particle size of tens of microns can be prepared, and the production efficiency is doubled. , The cost is reduced by 50%, and it is expected to be used as a raw material for titanium plate metallurgy Ti products.
2、Hydrodehydrogenation method. Due to the wide particle size range of the produced titanium plate, low cost, less strict requirements on raw materials, and easier technology completion, this method has become the main method of producing Ti powder at home and abroad after years of improvement and promotion. However, the titanium plate prepared by this method often has a high content of O and N. China Northwest Nonferrous Metals Research Institute adopts hydrogenation dehydrogenation technology to hydrogenate ingots to produce high-quality titanium plates with low O, N, and Cl. It has excellent performance and is currently able to produce titanium plates with an O content of less than 0.20%. Titanium plates have been mass-produced and are expected to provide stable titanium-titanium plates for automotive titanium plate metallurgical parts. Japan's Toho Titanium Co., Ltd. used improved technology to prepare Ti powder with a particle size of less than 150 microns and an O content of less than 0.15%. On the basis of this research, Toho Titanium Co., Ltd. invested one billion yen to create a hydrodehydrogenation method with an annual output of 30 tons Ti powder production line.
3、Metal hydride recovery method. TiCl4 can be restored by hydrogen at 3500°C, and TiO2 can be restored by carbon heat above 1800°C. In order to lower the reaction temperature, scientists from the former Soviet Union proposed to restore TiO2 and TiCl4 with CaH2, which can be carried out at a temperature of 1100-1200 °C, and the reaction will generate TiH2, and then remove H to obtain Ti powder. Because there is no Cl element to participate in the reaction in this method, titanium plates with extremely low Cl content can be obtained. It is said that its cost is only one-third of the traditional hydrodehydrogenation method, and it has already reached the level of planned production of (Baoji Lihua Nonferrous Metals). Although the Ti powder produced by this method has a higher H content, it is reported that the presence of a small amount of H is beneficial to the sintering of the titanium plate and improving the microstructure, and can be completely removed in the subsequent vacuum sintering and annealing process.
