Niobium C103 alloy is an important high temperature resistant material, which is widely used in aerospace and nuclear industry. Because of its excellent high temperature strength, oxidation resistance and corrosion resistance, niobium C103 wire has important applications in the manufacture of rocket engines, thermocouples and high temperature heating elements. The following are the main processing methods of niobium C103 wire:
First, casting and hot processing
Smelting and casting
Vacuum induction melting (VIM) : The melting of niobium C103 alloys is usually carried out in a vacuum induction furnace to prevent oxidation and the introduction of impurities at high temperatures. The vacuum environment is conducive to obtaining high purity niobium alloys.
Ingot: molten liquid alloy is formed into ingot by casting process to provide raw materials for subsequent processing.
forge
Hot forging: The ingot is forged at a high temperature of around 1200°C to improve its internal structure and mechanical properties. The forging process requires strict control of temperature and deformation rate to avoid cracks and defects.
Two, cold processing
Hot extrusion
Preliminary forming: The forged blank is heated to the appropriate temperature and then hot extruded, so that it is initially formed into a finer bar or wire. This process is usually carried out in a protective atmosphere or vacuum environment to prevent surface oxidation.
Cold drawing
Multi-pass cold drawing: After hot extrusion, the bar needs to be cold drawn multiple times to gradually reduce its diameter and increase its length. After each pass of cold drawing, intermediate annealing is usually required to eliminate work hardening and improve the plasticity and workability of the material.
Lubrication and cooling: During the cold drawing process, the use of appropriate lubricants and coolants can reduce friction and heat accumulation, thereby improving processing efficiency and surface quality.
Intermediate annealing
Intermediate annealing process: In the multi-pass cold drawing process, intermediate annealing is required after each drawing several passes. Intermediate annealing is usually carried out in a vacuum or inert gas environment between 800°C and 1000°C, with the aim of eliminating processing stress and improving the ductility of the material.
Third, surface treatment and finishing
Surface cleaning
Pickling: Cold-drawn niobium C103 wire is usually coated with oxide and processing residues, which can be removed by pickling (such as using a mixture of hydrofluoric acid and nitric acid).
Mechanical polishing: The pickling silk can be mechanically polished to obtain a smooth surface and improve the surface quality of the finished product.
Annealing treatment
Final annealing: The finished wire is subjected to final annealing before delivery. The annealing temperature and time need to be precisely controlled to ensure uniform microstructure and excellent mechanical properties of the filament.
Quality inspection and control
Nondestructive testing
Ultrasonic inspection: Ultrasonic inspection is carried out on the wire to detect internal defects and cracks to ensure the internal quality of the material.
Eddy current testing: Surface and near-surface defects can be found through eddy current testing to improve product quality and reliability.
Mechanical property test
Tensile test: test the tensile strength, elongation and other mechanical properties of the wire to ensure that it meets the requirements of use.
Microstructure observation: The microstructure of a material is observed through a metallographic microscope to assess its internal structure and uniformity.
Sum up
The processing method of niobium C103 wire involves melting, casting, hot forging, cold drawing, surface treatment and quality inspection. Each link requires strict control of process parameters to ensure that the final product has excellent performance and quality. With the continuous advancement of technology, the processing process of niobium C103 wire is also continuously optimized to meet higher application requirements.