1. TIG welding
TIG welding is in inert gas environment such as argon, so that the tungsten electrode and the mother material between the arc, so that the mother material and add welding material melting, welding method.
2. DC TIG and AC TIG
DC TIG Welding power supply is used as welding power source, the electrode is negative (rod negative, en polarity), the mother material is a positive welding method, widely used in stainless steel, titanium, copper and copper alloy welding.
AC TIG Welding
With AC arc welding power supply, the electrode and the positive polarity of the base material change with each other. When the rod is positive (DC reverse mode), it has the effect of cathodic atomization, which can remove the oxide film on the workpiece surface.
Aluminum and aluminum alloy surface has a layer of dense oxide film ($literal, melting point 2050 ℃, aluminum melting point only 660 ℃) covered on the surface of the molten pool, easy to cause slag and not fusion and other defects, can use the reverse polarity of the cathode crushing effect to clear. However, when the DC is reversed, the tungsten electrode burns badly and the AC arc welding is generally used. AC arc welding is generally applied to the weld of aluminum and magnesium.
3. Type and use of tungsten electrodes used in TIG welding
Tungsten electrodes even the same electrode diameter, according to the use of different welding power supply (DC, AC, DC polarity, pulse control), AC tig welding cleaning width adjustment, etc., tolerance current is different. If the sample is not used and the tolerance current required in the instruction manual is used, the overheating of the tungsten electrode will lead to the problems of melting, poor arc-arcing and unstable arc.
4, the advantages and disadvantages of TIG welding:
Can be welded almost all industrial metal and alloy welding quality good gas protection effect, can achieve fine welding forming good, no need to clear the slag no splash, no smoke can be widely applicable to thin plate and non-ferrous metals welding in a windy place to use difficulties, protect the gas your welding speed is slow.
Low carbon steel, Al, SUS, copper and copper alloys, titanium, magnesium and so on.