Welding is the joining of materials based on the principles of magnetic bonds between atoms of the two materials to be joined. Excess welded joints are lightweight construction, can withstand high strength, easy implementation, and quite economical. However, the main drawback is the change in the microstructure of the material being welded, resulting in changes in physical and mechanical properties of the material being welded.
Macro metal welding processes are classified into two groups, namely: (1) Liquid state welding (LSW), and (2) Solid state welding (SSW). LSW is a metal welding process is done in a liquid state, while the SW is a welding process in which the welding current, the metal in the solid state. Welding metals LSW and WSW have some techniques / methods. Various types of welding based methods.
A. (Liquid State Welding)
1. (Electric Arc Welding)
a) (Flash Butt Welding)
Flash butt welding is a method performed by combining the electron jumps to the pressure, where the welded workpiece heated by stepping electron energy is then pressed with a tool so that the materials are welded together well.
b) (Consumable Electrode)
Consumable electrode (electrode terumpan) is a welding electrode welding which also serves as an added ingredient. Terumpan welding electrodes consist of:
- MIG (Metal Inert Gas) and MAG (Metal Active Gas)
MIG welding electric arc welding is also where the heat generated by an electric arc between the electrode tip and the base material, due to the electric current and use electrodes shaped in the form of a coil of wire that moves rollers arranged by the couple gear-driven electric motor.
Electrode movement speed can be adjusted as necessary. Nosal Ias stalk fitted with protective metal to eject gas drained from gas bottles malalui gas hose.
- Electricity (Shielded Metal Arc Welding / SMAW)
SMAW (Shielded Metal Arc Welding) is a welding process to melt the base material that uses heat from the electricity through the tip electrode with a protective form of flux or slag melt when participating pengelasan.Prinsip of SMAW is to use heat from the arc to melt the base metal and the tip of a consumable electrodes covered with a voltage 23-45 Volt electricity used, and the use of electrical current to melt up to 500 amperes are commonly used ranged from 80-200 amps.
- Arc Welding Unexpressed (Submerged Arc Welding / SAW)
This is the basic principle welding uses an electric current to generate the arc (Arc) so as to melt the weld filler wire (filler wire), in welding SAW weld metal is submerged in the liquid flux contamination from the air, which then flux will form a slag welding ( slag) are strong enough to protect the weld metal to freeze.
c) (Non Consumable Electrode)
Non-consumable electrode welding using electrodes are, where the electrode is not functioning as an added ingredient. Electrodes serve only Him as power plants, while the use of filler material added metal.Non Consumable Electrode consists of:
- TIG (Tungsten Inert Gas)
TIG welding (Tungsten Inert Gas) welding is the process of electricity generated by the flame dimanabusur tungsten electrode (electrode no terumpan) with a metal workpiece. Regional dilindungioleh welding gas reserves (gas off) so as not to get contaminated denganudara outside. Welding wire can be added or not depending daribentuk connection and thickness of the workpiece to be welded.
- Plasma
2. Resistance (Resistance Welding)
a) (Spot Welding)
Welding is done by running down the workpiece by an electric current through the electrode, due to the barrier between the two materials to be joined, then the heat can melt the raised surface of the material and the stress builds connections
b) Kelim (Seam Welding)
Judging from the principle works, welding seams with spot welding, which is different electrode shapes. Cylindrical electrode welding seams.
c) or Carbide Gas (Oxy-acetylene welding / ÖAW)
Welding with oxy - acetylene welding is the process manually by heating the surface of the metal to be welded or connected by a gas flame until melted through the burning acetylene gas C2H2 with O2 with or without filler metal.
d) Las Sinar Laser
Laser beam welding is a welding memanfaaatkan laser light waves that are drawn straight ahead with no spread to the workpiece to produce heat and melting the metal to be welded.
e) Electron beam
The principle works is the heat energy obtained from the energy of an electron in the collision on the workpiece, the electrons emitted by the cathode to the anode is focused by the lens into the electrical system of deflection. Electron beam deflection system that has been continuing to focus on the work piece. Rays that are the focus used to perform welding work piece.
B. Conditions Solid (Solid State Welding)
1) Friction Welding
Friction welding or friction welding a metal splicing process by utilizing heat energy caused by the friction of two materials to be spliced
2) Cold Welding
Welding cold (cold welding) welding is carried out in the cold. That is cold here, does not mean there is no heat, heat can occur from the process, but not exceeding the recrystallization temperature of the metal being welded. Cold Welding consists of:
- Ultrasonic (Ultrasonic Welding / UW)
Ultrasonic welding is a solid connection process for similar metals, as well as different kinds of metals, which generally forms its connection is a connection overlap. High-frequency vibration energy-welding the weld area's with the direction parallel to the joint surface. Oscillatory shear stress on the surface of the weld-weld caused by the application of force, it will break and tear the existing oxide layer on the second surface of the parent metal to be welded.
- Explosion (Explosive Welding / EW)
Explosion welding or welding is often called bandaging (clading welding), is a welding process where the two surfaces into one under the influence of collisions (impact force) with high pressure from the explosion (detonators) are placed close to the parent metal.
3) Forging
Joining metal by the end of this is done by heating the metal to be connected later forged, then there was a connection. Heat takes a little above the recrystallization temperature of the metal, so the metal is still in.
