1. Copper has excellent electrical conductivity, thermal conductivity, corrosion resistance, ductility and certain strength. Widely used in the electrical, electronic, chemical, food, power, transportation and aerospace industries. Adding more than 10 kinds of alloying elements to pure copper (copper) to form solid solution of various copper alloys, such as adding zinc to brass; adding nickel to white copper; adding silicon to silicon bronze; adding aluminum to aluminum bronze and the like. Tool Bag,Waterproof Tool Bag,Tool Kit Bag,Tool Tote SUZHOU NEWSTAR HARDWARE CO.,LTD. , https://www.hardwarenewstar.com
2. Copper and copper alloys can be connected by brazing, electric resistance welding and other processes. In today's industrialized development, fusion welding has dominated. Copper and copper alloys are easily welded by electrode arc welding, TIG welding, MIG welding and other processes.
3. There are four main elements that affect the weldability of copper and copper alloys: one is the effect of high thermal conductivity. The thermal conductivity of copper is 7 to 11 times larger than that of carbon steel. When the process parameters are similar to those of the same thickness of carbon steel, the copper is difficult to melt, and the filler metal and the base metal are not well fused. Second, the welded joint has a high thermal cracking tendency. During welding, the copper in the molten pool forms impurities with low melting point eutectic, which makes the copper and copper alloy have obvious hot brittleness and generate hot cracks. Third, the defects that produce pores are much more serious than those of carbon steel, and they are hydrogen holes. The fourth is the change in the performance of the welded joint. Grain coarsening, plasticity decline, corrosion resistance, etc.
4. Pure copper (copper) can be welded with "Copper 107" welding rod, using Panasonic 400AT2, 400/600SS DC arc welding machine, DC reverse connection. Before welding, the workpiece must be preheated at 400-600 °C to ensure good welding of the filler metal and the base metal. Silicon bronze, aluminum bronze, and phosphor bronze electrodes can also be used to apply the same copper alloy structure with the same chemical composition.
5. DC TIG welding process is widely used in the welding of copper and copper alloys. The welding air is well formed, and the quality is good inside and outside. Under the protection of argon gas, the molten pool is pure, the pores are less, the thermal cracking effect is small, and the operation is easy to master. When the thickness is ≤ 4mm, it can be preheated before welding, and it can be preheated directly with argon. When the temperature of the molten pool is close to 600 °C, the filler wire can be added to melt the base metal to achieve welding. For copper with a thickness greater than 4 mm, pure copper should be preheated at 400-600 °C. Copper alloy welding preheating 200-300 °C. 300TSP, 315TX DC TIG welder can weld copper alloys such as pure copper, silicon bronze, phosphor bronze, brass and white copper. The 300WP5, 300/500WX4 AC/DC dual-purpose TIG welder can use AC TIG welding aluminum bronze (clearing the surface oxide film with AC square wave) and soldering the above copper material with DC TIG.
6. In recent years, more and more constructions have been used to weld copper and copper alloys by MIG method, especially for aluminum bronze, silicon bronze and white copper with thickness ≥ 3 mm. MIG welding is almost always required for copper and copper alloys with a thickness of 3~14mm or >14mm, because of high deposition efficiency, large penetration depth and fast welding speed (generally 3~4 times of TIG welding), achieving high efficiency, high quality and low The economic benefits of cost. Before the copper welding, the preheating temperature requirement (pure copper 400~600°C, copper alloy 200~300°C) should be achieved. The welding wire is chemically similar to the parent metal, and the argon purity is ≥99.98%. Tangshan Panasonic 500RF2 waveform control, 500AG2 inverter pulse MIG/MAG welding machine is suitable for the above-mentioned copper and copper alloy gas metal arc welding process requirements.