Pure nickel wire has high chemical stability, good oxidation resistance and corrosion resistance, and has been widely used in electronic and electrical industry. At present, there are a variety of pure nickel wire production processes at home and abroad, but the main production process is roughly the same, which is described as follows: electrolytic nickel plate - shear - induction furnace melting - casting ingot - ingot peeling - heating - forging - forging repair - heating - heat treatment - pickling - cleaning - drawing - semi-finished wire - annealing - drawing - finished nickel wire.
The heating and rolling temperature of electrolytic nickel plate is 900~1040℃, the holding time is 1~4 hours, the rolling deformation is 60~90%, the heating temperature is high, the holding time can be shortened, and the rolling deformation can be larger.
The nondestructive testing method can adopt X-ray testing, ultrasonic testing, magnetic particle testing, etc. Ultrasonic flaw detection method is preferred.
Cold rolling process, its shape variable is 10~50%; The annealing treatment after cold rolling is the use of protective atmosphere continuous annealing furnace for heat treatment, heating temperature of 800~950℃, annealing speed of 0.8~1.5 m/min, in which the thicker the thickness of the annealed nickel strip, the higher the annealing temperature, the slower the annealing speed.
The cold drawing process is to use different specifications and sizes of die to pull the segmented nickel strip multiple times to the size of the semi-finished nickel wire. The annealing treatment of the finished nickel wire is carried out by a protective atmosphere continuous annealing furnace for heat treatment, the heating temperature is 750~900℃, the annealing speed is 1.8~4.0 m/min, the larger the diameter of the annealed nickel wire, the higher the annealing temperature or the slower the annealing speed.
The invention adopts heating rolling method. On the one hand, heating can play the role of degassing pretreatment, remove harmful gas in electrolytic nickel plate, and improve material purity; On the other hand, the large deformation of hot rolling can break the coarse crystalline particles in the electrolytic nickel plate, refine the grain, and improve the processing property of the material; The invention adopts direct rolling of electrolytic nickel plate without melting and forging, avoiding the infiltration of impurity elements and ensuring the purity of the material. At the same time, the production cycle is short and the production cost is low. Good economic benefits. It can produce high purity nickel wire with high purity (nickel content greater than 99.9%), less impurities, low resistivity and good electrical conductivity.
