TIG welding (tungsten arc welding) of light weight aluminum alloy is to utilize a big amount of heat generated by the formation of an arc between tungsten electrode as well as the workpiece to thaw the light weight aluminum material, and then fill the welding cable to obtain a firm welding joint. The tungsten electrode and weld location are protected by inert gas from the nozzle to prevent reaction in between the weld area and the surrounding air.
TIG welding appropriates for welding aluminum alloy sheet with a thickness of less than 3mm, its contortion is dramatically much less than gas welding as well as hand arc welding. Air Conditioning TIG welding cathode can www.weldermetals.com successfully cleanse the oxide film, without the use of change to prevent welding residue as well as slag deterioration. Its joint kind is not restricted, will certainly produce great joints creating and bright look. The disintegration of the welding component by argon gas accelerated the cooling, boosted the structure and also performance of the joint, appropriate for all-position welding.
AC TIG welding as well as Air Conditioning pulsed TIG welding are one of the most frequently made use of approaches for welding light weight aluminum alloys, followed by DC reverse TIG welding. AC welding of aluminum alloy can attain the most effective suit in the present bring capability, arc control and arc cleansing. When straight current link (electrode connection), heat is generated externally of the work surface and developing deep infiltration. Although rarely utilized DC opposite link (electrode positive) TIG welding approach to bond aluminum, however this approach is showed efficiently in constant welding or repair welding thin-walled heat exchanger, pipe density below 2.4 mm, will certainly use a great melting deepness and also arc very easy to manage.
( 1) Tungsten electrode
Tungsten is the metal with the greatest melting point.
Tungsten has a strong electron discharge capacity at heat. When the tungsten electrode is added with the oxides of trace unusual earth aspects such as thorium, cerium, zirconium, etc., the electron emission is considerably minimized and also the present lugging ability is improved. Throughout TIG welding of aluminum alloy, tungsten electrode is mainly used to carry out current, sparks arc and maintains arc burning typically. Commonly utilized tungsten electrode products include pure tungsten, thorium tungsten and also cerium tungsten.
Welding process specification
In order to get superb weld creating as well as quality, according to the density of aluminum alloy plate, the welder must initially pick tungsten electrode size and form, welding wire diameter, securing gas as well as circulation rate, nozzle aperture, welding current, arc voltage and also welding rate, and after that fairly change the welding process parameters according to the real welding effect. The primary technical specifications of manual TIG welding of aluminum alloy consist of existing, electrode, shielding gas circulation price, tungsten electrode extension length, distance in between nozzle and work surface, etc. But for automatic TIG welding, the arc voltage (arc length), welding rate as well as cable feeding rate are the most crucial variables.
Parameters of TIG light weight aluminum alloy welding:
1) Nozzle aperture and safety gas circulation.
The nozzle aperture of aluminum alloy TIG is 5 ~ 22 mm, as well as the protective gas flow is generally 5 ~ 15L/min.
2) Tungsten electrode extension length as well as the distance in between nozzle and also workpiece.
Tungsten extension length of butt weld is normally 5 ~ 6, fillet weld is generally 7 ~ 8. The distance from the nozzle to the workpiece is typically about 10 proper.
3) Welding current.
This depends upon welding voltage, thickness, joint type, welding location and welder ability.
Handbook TIG welding utilizing A/C power supply, welding thickness of much less than 6 aluminum alloy, the maximum welding current can be established according to the electrode size D according to the formula I= (60 ~ 65) D. The arc voltage is primarily established by the arc size, which is usually about equivalent to the tungsten diameter.
4) Welding rate.
TIG welding of light weight aluminum alloy should adopt much faster welding speed in order to lower contortion. The general handbook TIG welding speed is 8 ~ 12m/h; In automatic TIG welding, the welding rate is generally unchanged during the welding process after the parameters are established,.
5) The dimension of the light weight aluminum alloy welding cable.
It is generally determined by aluminum plate thickness and also welding existing, as well as the size of the welding cable is proportional to them.