1、 Wire drawing
　
1. Wire drawing: Under a certain tensile force, a metal rod undergoes a plastic deformation process in which the cross-sectional area decreases and the length increases through a series of gradually decreasing die holes. Simply put, wire drawing refers to the stretching of a metal wire at an equal volume of wire length.
　
2. The mold used to achieve metal deformation during wire drawing is called a wire mold or wire drawing mold.
　
3. The four working areas of the wire drawing mold and their functions:
Lubrication area: Lubricant stays here and is brought into the work area.
⑵ Work area: Metal deforms here, reducing diameter and increasing length.
(3) Sizing zone: Ensure that the size of the pulled wire is accurate, the shape meets the requirements, and the mold should have a certain lifespan to prevent rapid wear and tear, causing the diameter to exceed the tolerance.
(4) Exit area: Do not scratch the wire coming out of the sizing area. At the same time, to prevent wire breakage caused by wire reversal when the pulling machine stops in the middle.
　
4. The requirements that the wire drawing mold should meet:
(1) Ensure that the size, shape, mechanical properties, and surface quality of the pulled wire meet the standard requirements.
⑵ Each deformation should be as large as possible, making full use of metal plasticity to improve production efficiency.
⑶ Ensure sufficient safety factor by avoiding wire breakage and thinning.
　
5. Function and temperature (concentration) control of wire drawing oil
The main function of wire drawing oil is to lubricate and cool the metal wires and molds during the drawing process; At the same time, remove the metal powder generated during the compression deformation process of the metal wire. It plays a role in improving the surface quality of metal wires and extending the service life of molds.
⑵ Temperature control of wire drawing oil: The optimal working temperature for aluminum drawing is 40-50 ℃, and the maximum temperature does not exceed 60 ℃; Copper pulling<40 ℃.
⑶ Copper soap solution concentration: 3-8%, pH value 7.5-8.5
(4) Copper pulling cooling water concentration: 0.5-1%, outlet temperature not exceeding 55 ℃, and inlet temperature not exceeding 33 ℃.
Copper wire drawing oil is made with low viscosity mineral oil as the base oil and various additives added. Its main ingredients include various additives such as amide soap, synthetic ester, surfactant, rust inhibitor, sizing agent, antioxidant, mold and preservative, defoamer, etc. of natural oils and fats.
　
6. The main characteristics of copper wire drawing oil include:
a. Good lubrication performance, strong lubricating film strength, which can reduce the wear of high-speed copper drawing machine wheels and wire drawing molds;
b. Low foam, good cooling effect, good oxidation resistance to copper, and processed copper is not easy to oxidize;
c. Good cleaning performance, which can effectively prevent the adhesion of copper soap in the wire drawing die, drum, bearing, and chassis, and extend the service life of the wire drawing die and drum;
d. Good stability, less prone to odor and deterioration, long service life, and cost savings;
e. Safe and hygienic, non-toxic and odorless, with no irritating effect on the skin, and normal use without adverse effects on the human body;
 
7. Main characteristics of aluminum wire drawing oil:
Aluminum wire drawing oil is prepared from petroleum lubricating fractions as raw materials through solvent refining and clay treatment processes to obtain refined base oil, and is blended with various oily additives such as antioxidant, rust proof, anti wear, defoaming, and low-temperature pour point reduction. The main characteristics of aluminum wire drawing oil are:
a. Good lubricity, can improve the surface smoothness of aluminum wire and reduce mold wear;
b. Good stability, strong aging resistance, long service life, less prone to deterioration and odor;
c. Good oxidation stability, thermal stability, rust and corrosion resistance, and extreme pressure friction resistance;
d. Safe and hygienic, this product is non-toxic and odorless, has no irritating effects on the skin, and has no adverse effects on the human body when used normally;
 
8. The biggest difference between copper and aluminum wire drawing oils
When copper wire drawing oil is used in actual wire drawing, a certain proportion of water is added to the original liquid of the wire drawing oil for modulation, and its concentration should meet the requirements of our process regulations. The water content in aluminum wire drawing oil is strictly controlled, and the water content in aluminum wire drawing oil should be less than 0.2%.

2、 Annealing
　
1. Purpose of annealing:
1) Restore the plasticity after cold work hardening to the level before cold working, so as to continue processing.
2) In order to restore the mechanical and electrical properties of the finished product of the stay wire to those before the stay wire, annealing of the finished product is carried out.
3) In order to obtain high-strength wire, aluminum magnesium silicon alloy wire needs to be quenched and aged.
4) For finished aluminum wires, using appropriate processes can obtain semi hard wires with properties between hard and soft wires.
5) For copper brush wires, annealing is carried out after the bundle and twisting are completed to eliminate the internal stress caused by the bundle and twisting of single wires, making the finished product soft and applicable.
6) For alloy products that generate heat from the conductor itself in high temperature locations or during use, annealing is carried out in advance to avoid changes in electrical properties during use. The annealing temperature is slightly higher than the usage temperature and the annealing time is shorter.
　
2. Basic principles of annealing
After cold working plastic deformation, the metal undergoes internal grain fragmentation, lattice distortion, and residual internal stress, making it unstable. It has a spontaneous tendency to change towards a stable state. But at room temperature, the diffusion ability of atoms is weak, making it difficult to undergo changes. So, by combining
Heating the deformed metal increases the kinetic energy of the atoms, causing them to undergo changes and restoring the metal to its pre cold working level in the shortest possible time.
　
3. The basic process of annealing
1) Response stage
2) Recrystallization
3) Grain growth stage after recrystallization
　
Due to the loose surface oxide of copper, it can be continuously oxidized. Therefore, when annealing copper wires, it is necessary to use "bright" annealing, which means heating and annealing in an oxygen free vacuum or in an environment filled with inert gas. Common protective gases include:
1) Inert gases - helium (He), neon (Ne), argon (Ar), xenon (Xe).
2) Neutral gas - carbon dioxide (CO2), nitrogen (N2) or their mixture, water vapor.