The preparation method of fine crystal niobium titanium alloy, the Nb powder and TiH2 powder after ball milling mixed evenly, and then pressed forming, under the protection of argon hot pressing sintering, Nb Ti alloy. In the invention, Nb powder can further reduce its particle size after high-energy ball milling, increase internal defects and atomic activity, so as to promote the diffusion and combination of two kinds of atoms. By using TiH2 instead of Ti powder, H2 can be decomposed in the sintering process to further reduce the formation of impurities in the alloy. The grain size of the alloy prepared by the invention is 16 ~ 19μm, the microstructure is more uniform, and the density is up to 99.99%, which further improves the density while greatly reducing the grain size. A new method is provided for the preparation of fine crystal Nb Ti alloy.
The importance of sputtering target becomes more and more apparent in the sputtering technology, the quality of the target will directly affect the quality of the coating. As the characteristic size of metal interconnect develops to nanometer level, the width of metal interconnect decreases and the number of layers of metal interconnect increases, the traditional single metal target technology can not meet the current needs, so the demand for alloy target is increasing. Nb-Ti alloy is widely used as target material alloys because of its good thermal and electrical conductivity, high melting point, corrosion resistance and other physical properties. The properties of the alloy target are mainly determined by the density, grain size and microstructure of the alloy. Therefore, the coating quality can be greatly improved by increasing the density, composition uniformity and reducing the grain size of Nb-Ti alloy.
The specific process of Nb powder high-energy ball milling is as follows: Nb powder is put into the ball mill tank, about 10% alcohol is added as dispersant, stainless steel ball is added according to the ball material ratio of 10 ~ 30:1, and argon gas is injected into the ball mill after vacuuming the ball mill, and the sealed ball mill is put into the ball mill for 10 ~ 20h at the speed of 400r/min.
Mixing powder is to mix Nb powder and TiH2 powder after ball milling for 4h to ensure the uniform mixing, wherein the mass of Nb powder accounts for 45-50%, and the rest is TiH2 powder.
Pressing is the process of pressing a mixture of Nb powder and TiH2 into a green blank at a pressure of 1.5GPa.
Sintering is to put the green billet into the atmosphere protection hot pressing sintering furnace, temperature up to 500℃ for 30min, then temperature up to 920℃ for 5min, then temperature up to 970℃ for 30min, and finally temperature up to 1200 ~ 1300℃ and began to pressure, with 30MPa pressure for 2 ~ 3h. Finally with the furnace cooling. The obtained Nb-Ti alloy is protected by argon gas throughout the whole process.
