Aluminium welding

In spot or resistance welding, strong pressure is applied to a relatively small area. Electrodes provide a large amount of energy as an electric current. Local melting of the aluminium sheets between the electrodes leads to a strong joint between the components.

The KUKA.Robospin application software optimises the spot welding of aluminium joints. The special feature is that the robot movies in a circle around the weld while welding. This reduces contact resistance and lowers the aluminium alloying of the electrode tips.

Advantages

• Improved weld quality

• Longer electrode tips

• Time savings because of less frequent tip dressing or changing of electrode tips

Both TIG and MIG processes require clean surfaces to avoid porosity. Gas metal- arc welding is a type of arc welding process. In this processes, an electric arc forms between an electrode and the workpiece. This arc melts the workpiece and, if required, a filler metal to join them together. In aluminium arc welding, an inert gas flows around the electrode and the weld pool. This creates a shield to stop a unwanted chemical reactions between the oxide and molten material. Choosing the right electrical settings and shielding gas can directly affect seam formation, weld pool temperature and welding speed.

MIG welding (metal inert gas welding): In MIG welding processes, a melting aluminium welding wire is used as an electrode. This filler metal serves to bridge gaps, if necessary, or increase the strength of the joint. The choice of aluminium alloy for the filler wire can affect the joint's properties in MIG welding. Argon is the most commonly used shielding gas in welding aluminium, often essential in MIG welding aluminium. MIG welders work well for thicker pieces of aluminium steel. This is because MIG welding thin pieces can cause burn-through. A TIG Welder is best suited for thin materials to prevent burn-through. The minimum aluminium thickness for MIG welding should be 14 ga to 18 ga. If the alloy is thinner TIG welding is the more appropriate process.

TIG welding (tungsten inert gas welding): In this process, a burning arc forms between the aluminium part and a tungsten electrode that does not melt. TIG robotic welding uses alternating currents. It has a high-frequency electrode that does not touch the alloy. This helps reduce contamination and remove impurities during TIG welding aluminium. 

Plasma welding: Plasma welding is a type of TIG welding. In this process, a water-cooled nozzle narrows the arc. An etxra plasma gas is also added. This creates a focused arc with higher energy density. It also impedes oxide formation creating a strong aluminium alloy weld seam. A TIG Welder's control helps produce high quality welds. 

Advantages of the process

• High welding speed

• First-class aluminium weld seam

• High deposition efficiency and welding depth

• Simple handling 

Application 

• Wide range of materials and material thicknesses

Friction welding is a joining process that produces full-surface contact joints. Rotating one workpiece under pressure against another workpiece creates friction. This creates heat between the two surfaces and plasticizes the material. No filler materials, additional flux or shielding gases are required for processing the alloys.

Advantages of the process

• Exceptional joint quality

• Fully homogeneous joint over the entire joint area

• Joining of different metals

• Materials do not melt

• Increased speed and joint integrity

Application

• Material with low melting temperature 

• Rotationally symmetric components