Copper rod refers to solid copper rod material formed through extrusion or drawing.
There are many types of copper rod, including copper rod, brass rod, cupronickel rod, and bronze rod.
Copper rod forming has its own unique principles. The copper rod forming process can also be described as the copper rod production process. Different types of copper rod require different forming processes and have different characteristics.
What materials are copper rods made of? Copper rod materials include H59, H59-1, H59-2, H59-3, H60, H60-2, H62, H63, H65, H68, H70, H80, and H90; C1100, C1020, C2680, C2800, C2600, C2801, C5191, C5210, C2200, C7521, C7541, C17200, C1070, C7701, QSn6.5-0.1, QSn8-0.3, QSn4-0.3, BZn18-18, BZn15-20, and CuBe2.
Before introducing the copper rod forming process and procedures, let's discuss the various metal forming processes.
1. Metal solidification forming is conventionally referred to as casting. Casting is a process in which molten metal is poured, injected, or drawn into a mold cavity and, after solidification, is used to produce a casting with a specific shape and properties.
2. Metal plastic forming is a processing method that utilizes the plastic deformation capacity of metal materials to produce a desired plastic deformation under the action of external forces, thereby producing a part or blank with a specific shape, size, and mechanical properties.
This process is generally categorized as free forging, die forging, sheet metal stamping, extrusion, and pressing. In engineering, the forgeability of a metal is often used to characterize its performance. Forgeability is often measured by the metal's plasticity and resistance to deformation. High plasticity and low resistance to deformation indicate good forgeability; conversely, poor forgeability indicates poor forgeability.
3. Metal welding. Welding is a forming process that uses heat, pressure, or both, with or without filler materials, to achieve atomic bonding of metal materials. Common classifications include fusion welding, pressure welding, and brazing.
So, what are the forming processes for copper rods? There are many copper rod forming processes, including extrusion, rolling, continuous casting, stretching, etc.
Copper rod forming process flow? There are three copper rod forming process flows, as follows
1. Pressing - (rolling) - stretching - (annealing) - finishing - finished product.
2. Continuous casting (upper pull, horizontal or wheel type, crawler type, dipping) - (rolling) - stretching - (annealing) - finishing - finished product
3. Continuous extrusion - stretching - (annealing) - finishing - finished product.
Extrusion of copper rod forming process?
1. Types of extrusion: Extrusion is divided into three types: forward extrusion, reverse extrusion and special extrusion.
(1) Forward extrusion: refers to the extrusion behavior in which the extrusion direction of the product is the same as the direction of the extrusion force.
(2) Reverse extrusion: The extrusion direction is opposite to the direction of the extrusion force.
(3) Special extrusion: refers to other extrusion methods such as hydrostatic extrusion.
2. Characteristics of extrusion:
(1) Characteristics of forward extrusion: Among them, forward extrusion equipment is relatively simple and is the most widely used. (2) Characteristics of directional extrusion: Reverse extrusion reduces the friction between the ingot and the extrusion barrel, reduces the extrusion force, and can increase the tool life. It is widely used in small and medium-sized extruded products. 3. Precautions for extrusion: During the extrusion process, the ingot is subjected to three-dimensional compressive stress in the extrusion barrel and can withstand a large amount of deformation. During extrusion, the mold should be reasonably designed and the extrusion process parameters should be selected according to the characteristics of the alloy, the specifications and technical requirements of the extruded product, and the capacity and structure of the equipment. This includes the specifications of the ingot, the extrusion ratio, the extrusion temperature, the extrusion speed, etc. In order to ensure and improve the surface quality of the extruded product, copper alloys are often extruded by peeling extrusion to remove defects on the surface of the ingot. For precipitation-strengthened alloys, water seal extrusion can be used to achieve solid solution treatment before cold deformation in the extrusion process. Quantongwang experts said that for ordinary alloys, water seal extrusion can reduce surface oxidation of the product and avoid re-pickling of the product. Horizontal forward extrusion is the most traditional and common extrusion method. The main problem when it extrudes pipes is the double core of the pipe. Reverse extrusion not only reduces eccentricity but also allows for the extrusion of longer ingots, increasing yield. Vertical extrusion minimizes eccentricity, but limits the length of the extruded product.
Continuous extrusion offers a short process flow, heavy rolls, and the ability to produce long products. It is particularly suitable for the production of products with special cross-sections. The product yield rate is high, reaching 90-95%. It also reduces metal consumption, energy consumption, equipment investment, and footprint, making it easy to operate continuously and environmentally friendly.
With technological breakthroughs in continuous extrusion technology for product width, this method is now being developed and applied in the production of oxygen-free copper and pure copper strip. The main drawback of this method is its short die life. Improvements in die design and the lifespan of the die material are crucial.
What are the three types of copper bar rolling processes? Copper bar rolling can be performed by grooved rolling, spinning rolling, and planetary rolling.
Is stretching part of the copper rod forming process?
1. Definition of stretching: Stretching involves passing a blank through a die and applying tension to change its shape and dimensions. It is a key process in the production of finished copper rod and wire.
2. Characteristics of stretching: This process ensures that the product's shape and dimensions meet the required specifications, with high dimensional accuracy and excellent surface finish.
3. Rod and wire stretching is a diameter-reducing stretching process. Tube stretching can be categorized as expanding, reducing, or reducing both diameter and wall. The mandrels used in tube stretching include fixed, floating, and long mandrels.
During floating mandrel stretching, the mandrel's shape creates a force balance, stabilizing it within the deformation zone. This method offers a high per-pass elongation coefficient and significant diameter and wall reduction, making it suitable for the production of long tubes and coils. Fixed mandrel stretching requires a mandrel to maintain the mandrel's stability within the deformation zone and is primarily used for the production of shorter, straight tubes. Commonly used stretching equipment includes chain stretchers, disc stretchers, hydraulic stretchers, and combined stretchers. Chain stretchers are primarily used for stretching straight bar products and are categorized as single-chain, double-chain, single-wire, and multi-wire stretchers. Disc stretchers are primarily used for producing small and medium-diameter coils. Combined stretchers primarily produce small-sized coils into fixed-length straight bar products. They can simultaneously perform stretching, straightening, surface polishing, and cut-to-length processes, directly producing the finished product.
What is the heat treatment process for copper rod forming?
The heat treatment of tubes, rods, and wires primarily involves intermediate annealing and final annealing. The annealing schedule is tailored to the alloy characteristics, product condition, and performance requirements.
Currently, bell-type furnaces, roller-hearth furnaces, and chain furnaces with specialized atmospheres are widely used for heat treatment of tubes, rods, and wires. While using a protective atmosphere, enhanced atmosphere circulation ensures a uniform atmosphere and a bright product surface. Through-type induction furnaces are primarily used for intermediate annealing of internally threaded air conditioning tubes. This process involves unwinding the coil, annealing it, and then re-coiling it, achieving continuous annealing from basket to basket. This equipment not only features gas shielding but also an internal pipe purge cleaning system.
Rod and profile heat treatment also includes quenching and aging. These are primarily used to heat treat alloys with age-hardening properties, improving their strength and overall performance. Extruded products are typically quenched using a water seal at the extrusion outlet, while drawn products require a dedicated quenching furnace.
Copper Rod Forming Process: Finishing?
Copper alloy tube, rod, and wire finishing primarily includes trimming (sizing), straightening, and surface treatment. Depending on the product specifications and requirements, trimming can be done by sawing or shearing. High-precision, large-format products are generally sawed. Straightness is a key quality indicator for tube and rod products. Commonly used straightening machines for pipes, bars, and profiles include roller straighteners, pressure straighteners, sinusoidal straighteners, and tension straighteners, with roller straighteners being the most widely used.
Roller straighteners straighten the product by repeatedly bending it over rollers of varying profiles. Tension straighteners clamp the product at both ends and apply opposing tension, causing slight deformation to achieve straightening. They are primarily used for straightening special profiles. Their elongation reaches 1-3%. Pressure straighteners are generally used for straightening large or extra-large bars, profiles, and thick-walled pipes. Sinusoidal straightening straightens small-diameter pipes and bars by repeatedly bending them over sinusoidal straightening rollers.
To ensure a clean and glossy finished surface, the product surface (including the inner surface of the pipe) requires surface treatment, which can be performed manually or automatically. Manual processing involves operators wiping away oil stains and dirt from the surface of the tubes and rods (including using compressed air to blow cotton balls into the tubes). Automated processing involves cleaning the tubes and rods with a liquid containing a cleaning agent (including blowing air into the tubes) and drying them.
What are the principles of copper rod forming?
1. All elements, without exception, reduce the electrical and thermal conductivity of copper rods. Elements that dissolve in the copper rod cause lattice distortion, leading to wave scattering during the directional flow of free electrons and increasing resistivity. Conversely, elements with little or no solid solubility in the copper rod have minimal effect on its electrical and thermal conductivity. It is particularly important to note that some elements have a drastic decrease in solid solubility with decreasing temperature. Precipitation as elemental elements or metallic compounds can both solid-solution and dispersion-strengthen the copper rod alloy without significantly reducing its electrical conductivity. This is a crucial alloying principle for the research of high-strength, high-conductivity alloys. It should be noted that alloys composed of iron, silicon, zirconium, and chromium with copper rods are extremely important high-strength, high-conductivity alloys. Because the effects of alloying elements on copper rod properties are additive, CoCr-Zr alloys are renowned for their high strength and high conductivity.
2. The microstructure of copper-based corrosion-resistant alloys should be single-phase to avoid the presence of secondary phases that can cause electrochemical corrosion. To this end, the added alloying elements should have a high solid solubility in the copper rod, or even be infinitely miscible. Single-phase brass rods, bronze rods, and white copper rods used in engineering applications all exhibit excellent corrosion resistance and are important heat exchange materials.
3. Copper-based wear-resistant alloys contain both soft and hard phases in their microstructures. Therefore, during alloying, it is important to ensure that the added elements not only dissolve in the copper rod but also precipitate hard phases. Typical hard phases in copper rod alloys include Ni3Si and FeAlSi compounds. The α phase should not exceed 10%.
4. Copper rod alloys that undergo polycrystalline transformations in the solid state exhibit damping properties, such as Cu-Mn alloys. Alloys that undergo thermoelastic martensitic transformations in the solid state exhibit memory properties, such as Cu-Zn-Al and Cu-Al-Mn alloys.
5. The color of copper rods can be altered by adding alloying elements. For example, by adding zinc, aluminum, tin, and nickel, the color changes from red to blue to yellow to white as the content changes. Properly controlling the content can produce gold-like and silver-like alloys.
6. Elements selected for alloying copper rods and alloys.
The company has a cluster of leading copper processing production lines in China, including:
German imported precision copper tube production line (annual output of 30,000 tons)
Japanese technology copper foil rolling line (thinnest up to 6μm)
Fully automatic copper bar continuous extrusion line
Intelligent copper sheet and strip finishing mill unit
Digitalized control and management of the whole production process is realized through MES system, and the dimensional accuracy of the products can reach ±0.01mm.
