Welding is a permanent connection of structures or devices made of plastic or metal. The metal parts are brought to a plastic state, i.e. pasty, by heating. Then they are joined by appropriate force without the use of binders. A small volume is plasticized only at the interface between plastics or metals. There may be different sources of heat. The most popular is resistance electric welding, i.e. resistance welding.
Types of welding:
- focal lengths
- water gas
- electric resistance
- butt spark plugs
Depending on the method, we first apply pressure, then warming up, or in the reverse order. You can also combine metals with ceramics.
Electric resistance welding
It involves bonding metals based on their natural properties, i.e. electrical resistance. Heat is released by means of electricity and pressure from the electrodes. The metal is melted and the parts are joined. Welding does not require a third metal, i.e. a filler metal. Electric resistance welding is, among other things, used to join sections or sheets. The quality of the joint depends on the clamping force as well as the amount of heat. In electric resistance welding, the most commonly used methods are spot, hump, butt and line welding. Many materials can be joined by electric resistance welding. Welding is widely used in industry. The following materials are welded: nickel, aluminium, titanium, copper, ferrous and non-ferrous metals.
Friction welding is also quite popular. In this method, the temperature is generated by surface friction. One element is fixed and the other is made to rotate. The phenomenon of particle diffusion as well as creep is important. Energy turns into heat. Adequate plasticity is created and the objects become immobile. Friction welding is a relatively new method, compared to other welding methods. This method is used in high-volume productions, such as aluminum rims, tools, car parts.