Study on extrusion technology of Niobium C-103 alloy ingot for aerospace

C-103 (NbHf10-1) alloy is a kind of low strength, high elongation alloy, the alloy has good cold plastic deformation and forming properties, excellent welding and coating properties, and has good high temperature performance. The tensile strength of the alloy between 1371 ℃ and 1482℃ is only 10% lower than that of Mo-0.5Ti alloy, but the specific strength is similar. The specific strength is the highest in the range of 1093~1427℃. Good plasticity and good machinability at a temperature as low as 200℃. These advantages make it a preferred thermal protection material and structural material in the aerospace industry, which is used to make combustor and nozzle of liquid rocket engine. Extensive foreign studies have been carried out on this alloy, and the extrusion temperature is recommended to be 1350~1450 ℃, but the higher the heating temperature, the more serious the oxidation of the alloy surface, and the coating materials, lubricants, mold materials are also difficult to solve. In order to overcome the above difficulties caused by high temperature extrusion. The extrusion of NbHf10-1 alloy ingot was studied at 1300 ℃. The results show that C-103 alloy with good surface quality and small dimensional tolerance can be extruded at 1150 ~ 1300 ℃. When NbHf10-1 alloy is extruded at 1150~1400 ℃ and extrusion ratio ≤5∶1, uniform size and good surface quality can be obtained. The extrusion constant of niobium C-103 alloy is 5 ~ 7 times of the tensile strength of the material at this temperature. Rolling niobium C-103 alloy sheet with extruded rectangular bar can improve the yield and production efficiency.