Copper Welding Is Difficult, Can Ordinary Welding Machines Handle It? Do You Need Any Special Techniques?

I. Ordinary Welding Machines Are Hard to Handle the Job, and Their Shortcomings Are Obvious

1. Ordinary Manual Arc Welding Machine: Almost Useless
• This type of welding machine relies on the heat generated by the burning of the welding rod. The heat input is insufficient to melt through copper materials. Moreover, there are almost no welding rods specifically designed for copper materials on the market. If you forcibly use other welding rods, the resulting weld seam will either be insecure or full of slag. It can only be used to temporarily patch a small hole. For proper copper welding, it is completely unreliable.
2. Basic DC TIG Welding Machine: Limited to Thin Pure Copper
• The basic DC TIG welding machine can barely weld thin-walled pure copper with a thickness of 1-3 mm, such as small copper terminal connectors. However, there are many problems: it lacks cathode cleaning function, which means it cannot remove the oxide film on the surface of copper materials, making it easy for slag to be trapped in the weld seam. The heat input control is not precise. When welding thicker copper materials, it will be "overwhelmed." It also cannot weld brass (the zinc in brass easily evaporates at high temperatures, causing the weld seam to become brittle).
3. Ordinary MIG Welding Machine: Prone to Burnthrough and Other Issues
• When welding copper materials with an ordinary MIG welding machine, a large current is required to melt the copper materials. However, a high current can easily burn through thin-walled copper materials. Moreover, using pure argon gas for protection is not effective in inhibiting the oxidation and gas absorption of copper materials. When welding brass, the evaporation of zinc is severe. This not only pollutes the environment but also reduces the strength of the weld seam, failing to meet quality requirements.

In summary, ordinary welding machines can only handle a small amount of low-demand thin-walled pure copper welding. To properly weld medium-thick copper materials, brass, or copper parts with strength and electrical conductivity requirements, professional equipment such as spot welding machines, laser welding machines, and robotic laser welding machines, along with special processes, are necessary.

II. Professional Equipment Is More Suitable, and the Right Choice Depends on the Scenario

1. Spot Welding Machine: The First Choice for Batch Spot Welding of Thin-Walled Copper Materials
• The copper spot welding machine relies on the pressure of electrodes and uses contact resistance to heat and melt local copper materials to form weld points. Its advantage is speed; each weld point only takes 0.1-1 second. It is particularly suitable for batch welding of thin-walled copper materials (0.1-2 mm), such as the connection of copper leads in electronic components and the assembly of small copper parts.
• However, it is important to note that you must choose a dedicated copper spot welding machine. Because copper has high electrical conductivity, it requires welding parameters of high current and short time to avoid false welding. The electrodes also need regular maintenance to prevent oxidation and wear from affecting welding quality.
2. Laser Welding Machine: Essential for High-Precision Copper Welding
• The laser welding machine uses a high-energy laser beam to melt copper materials. The heat-affected zone is very small, and it can precisely control the weld seam. The resulting weld seam is smooth and almost does not require post-processing. It has a wide range of adaptability and can weld pure copper and brass with thicknesses ranging from 0.05 to 6 mm. It is suitable for scenarios with high precision and appearance requirements, such as copper components in precision electronic devices and copper connectors in medical equipment.
• When welding copper materials, it is recommended to choose a laser welding machine with pulse function, which can reduce heat input and avoid deformation of copper materials. At the same time, it should be used with argon gas protection to prevent oxidation and gas absorption, ensuring the quality of the weld seam.
3. Robotic Laser Welding Machine: The Preferred Choice for Large-Batch Standardized Copper Welding
• The robotic laser welding machine is a combination of a laser welding machine and a robotic arm, which can achieve automated welding and can work continuously for 24 hours. Its welding precision is stable and will not be affected by human operation differences. It is suitable for large-batch copper welding, such as the welding of copper wire harnesses in the automotive industry and the batch welding of copper terminals in power equipment.
• It has a similar range of adaptability to laser welding machines in terms of copper material thickness and can also handle complex trajectory welding, such as the circumferential weld seams of irregular copper parts. It is particularly suitable for enterprises with large-scale production, which can greatly improve efficiency and reduce labor costs.

III. Special Processes Are Needed for Copper Welding, and Three Steps Ensure Quality

1. Before Welding: Thorough Cleaning Is Key
• The oil and oxide film on the surface of copper materials are potential welding hazards and must be cleaned thoroughly. Use acetone or alcohol to remove oil, sandpaper to polish or sulfuric acid to remove the oxide film from pure copper, and special cleaning agents to treat brass. If welding thick copper materials (more than 8 mm), preheat to 200-400°C before welding to slow down heat loss and avoid incomplete welding.
2. During Welding: Parameters and Protection Must Be in Place
• Adjust the parameters according to the equipment and type of copper material. For example, when using a laser welding machine to weld 3 mm pure copper, the energy density should be adjusted to the appropriate range. Protective gas is also essential. Use a mixture of argon and helium for pure copper welding, and a mixture of argon and 5%-10% nitrogen for brass welding, with a flow rate controlled at 20-25 L/min to prevent oxidation and gas absorption.
3. After Welding: Slow Cooling and Inspection Are Essential
• After welding, cover the weld seam with asbestos cloth to allow the copper material to cool slowly, reducing internal stress and avoiding deformation and cracking. For thick copper parts, low-temperature tempering (250-300°C for 1 hour) can further eliminate stress. Finally, inspect the weld seam to check for porosity, cracks, and conduct electrical tests as needed to ensure the quality meets the standards.

If you have welding machine requirements, please contact Ms. Zhao

E-Mail: pdkj@gd-pw.com

Phone: +86-13631765713