In the process of tantalum tube preparation, tantalum ingots are first cut by wire cutting. The wire cutting technology can improve the inner surface quality of tantalum hollow ingots, the coaxiality of the inner hole, reduce the wall thickness deviation and improve the comprehensive utilization rate of materials. The obtained hollow ingot was preheated to ensure that the anti-oxidation coating was evenly coated on the surface of the hollow ingot. Then, the surface of hollow ingots is coated with anti-oxidation coating, which effectively avoids contact with air in the process of processing tantalum hollow ingots and improves the surface quality of tube billet. Then, the hollow ingots coated with antioxidant coating are heated and squeezed again, and the hollow ingots are deformed to make the tantalum tube billets with fine and uniform grains. Then vacuum heat treatment was carried out on the tube billet after extrusion deformation. The heat treatment method could improve the purity and microstructure of the tube billet and reduce the surface pollution. The tube blank after vacuum heat treatment was rolled to ensure the size of the tube blank and the quality of the inside and outside surface, and to make the tube blank deformation uniform. Finally, the vacuum heat treatment was carried out, which effectively eliminated the residual stress and recrystallization structure in the process of material processing, and finally made the mechanical properties of the prepared tantalum tubes better.
In order to make the blank of niobium tube have better surface quality and comprehensive performance, the invention preferably adds oxidation treatment and burning on the material surface after rolling. In the process of preparing tantalum tubes, the processing procedures of wire-cutting - heating - coating anti-oxidation coating - heating - extrusion - vacuum heat treatment - rolling - vacuum heat treatment are carried out successively, so that the tantalum ingots can be deformed evenly, and the materials can be avoided from being polluted in the processing process, so that the surface quality of the prepared materials is better and the mechanical properties are higher.
Tantalum tubes were obtained by vacuum annealing at 1200℃ for 60 minutes. The obtained tantalum tube was subjected to flaring test: the tube segment with twice the diameter was cut off, and the inner diameter was expanded to 20% of the diameter with a flaring cone with a 60° cone Angle, without visible cracks on the surface. Or use the flaring cone with 45° cone Angle to expand the inner diameter to 18% of the diameter, with no visible cracks on the surface.
