Since about 5000 years ago , humans have been able to do welding . Welding is done by connecting the metal by heating the metal until it reaches two melting point of the metal . Then the two metals had to be stacked and then hammered to form a strong bond .
One piece of evidence is found in the valley area of the kingdom in 1922, which suggests that the coffin of King Tutankhamen is estimated to be made around 1360 BC with the involvement of the welding process .
Fire to heat the metal is obtained from burning wood or charcoal , this technique is called forging welding techniques . But in this way would be time consuming and not very practical . For centuries , welding forging is used as the main process to connect the metal without much experience growth .
The development of Welding Types
Elekctric Arc Welding
After electrical energy is found then the development of welding processes running at a rapid pace . In 1885 the means of electric arc welding ( Elekctric Arc Welding ) is found by Bernardes . Electric arc welding with electrode carbon rod without wrapping using the battery as a power source . The main drawback of electric welding process is the oxidation of carbon is high enough to cause the weld welding be easily corroded rust , so the welding technique is no longer used .
Resistance Welding
At the same time , precisely in 1877 , a British physicist named James Joule , find welding resistance ( Resistance Welding ) . In 1856 he heats two wire rods with electricity . During the heating process , the two wires are pressed to each other . It turns out the two wires attached to each other after over heated . Las prisoners achieve rapid development of various types of robots being created . Developed to meet the needs of the various forms of electrical resistance welding include spot welding , interval , seam ( lines ) and projection . This welding in the process applying heat and pressure . Electrode serves as a drain flow and pressure plate -shaped object being welded . In further developments , resistane welding produces several types of welding processes , such as welding flash ( Flash Welding ) in 1920 .
Thermit Welding
In the next decade , introduced Thermit welding ( Thermit Welding ) . Thermit welding is obtained by pouring molten metal between the two ends of the metal to be connected so it would melt . After the second freeze fused metal and liquid metal is poured serves as added ingredients .
Oxygen Acetylene Welding
Acetylene gas in 1892 was found by Thomas Leopard Wetson . Acetylene and oxygen gas mixture with ratio and pressure when burned will produce temperatures high enough to melt the metal . Oxygen gas is produced by liquefying air so pure oxygen can be taken . How this is done by Brins brothers, the French in 1886 . Tools for burning acetylene and oxygen gas mixture called brander , discovered by Fouche and Picord . This tool into use in 1901 . This welding wrought managed to shift the use of welding and welding processes dominate for several decades to develop electric welding .
In 1925 welding oxygen acetylene is shifted by an improvement in electric arc welding in which the arc welding electrode wear wrapped . After burning , wrapping electrode produces gas and slag . Gas protect welding crater of oxidation during the welding process is underway . Slag protects the weld during the freezing process to cool ( until the slag is cleaned ) . Limitations of arc welding electrode rod is limited so long ektode any given period should stop replacing welding electrode .
The starting point of weakness at the end of the 1930s created the electrode arc welding rolls . In principle , the welding does not need to stop before reaching the end of the weld lines . And welding can be performed by means of semi- automatic or automatic . Used as the protective flux . Flux poured shortly in advance so that the electrode electric arc flash by latent fluxes . The advantage , operators are not dazzled by the electric arc flame , weakness , limited welding position under hand only at other positions scattered flux will fall before the function .
Tungsten Inert Gas
In 1941 in the United States found Tungsten electrode . Tungsten is not melted by the heat of an electric arc flash that does not feed in the weld . Used as the protective gas core ( Inert ) which can last for a few moments on his condition . Core ejected gas to the welding area so that the weld avoid oxidation . Because it uses the core as a protective welding , welding is often called TIG ( Tungsten Inert Gas ) .
The success of the use of gas tungsten core on a pedestal at the base electrode also tried a roll in the early 1950s . This process is hereinafter referred to as Gas Metal Arc Welding ( GMAW ) or MIG welding ( Metal Inert Gas ) . Because the gas meter is very expensive then used a mixture of argon and oxygen gas or CO gas is quite active . Welding is commonly called the Metal Active Gas ( MAG ) . Can also be used protective argon mixtures with CO for no more than 20 % the result is quite good because it does not leave slag . Keep in mind that the protective gas is very expensive , so the only way is used for special purposes .
Flux Core Arc Welding
Next discovered electrode arc welding weld rolls with floured protector . In order to be used in all positions , electrodes made hollow like a pipe to put flux . This process is cheaper than the gas arc welding , can be for all welding positions and techniques can be developed in a semi- automatic or fully automatic welding is called flux cored arc welding ( Flux Core Arc Welding ) .
Stud Welding
Furthermore, there electrode as components to be mounted on the other . This is called welding stud welding. Stud mounted on the main body through the three stages of the layout position , the search ends and objects stud stud emphasis on primary and main object shortly after arc ignition is turned off .
Induction Welding
After that developed a high -frequency electric welding of 10,000 to 500,000 Hz . High frequency electric welding is often called induction welding . In terms of the process of unification of the object being welded , the welding including weld heat -assisted solid to break the oxidation layer or dirt on the surface of the object being welded . The heat generated is very thin on the surface of the object being welded so that it is suitable for welding thin plate .
Electron Beam Welding
In the 1950s , the electrical energy is converted into a beam of electrons is fired at the object to be welded . The heat generated is larger and electron former dimensions much smaller than the electric flame arc , the welding process is very fast so it is suitable for mass production . Hot region becomes more narrow so it is suitable for materials that are sensitive to changes in heat . Weld quality is very good and accurate , it's just very expensive equipment . This method is commonly referred to weld electron ( Electron Beam Welding ) .
Friction Welding
In 1950 , AL Chudikov , an engine from the Soviet Union , revealed the results of his observations on the theory of mechanical energy can be converted into heat energy . The friction on engine parts that move caused many losses because most of the mechanical energy is converted into heat generated . Chudikov argues , such a process should be used in the welding process . Once through experiments and research he managed to weld by utilizing the heat caused by friction . To increase the heat that occurs , not only the welded objects rotated , but also pressed one against the other . Pressure also serves accelerate fusion . This method is called friction welding ( Friction Welding ) .
Plasma Arc Welding
Plasma arc welding ( Plasma Arc Welding ) . The plasma process is actually a refinement of tungsten welding , flame electric arc just does not appear between the electrodes with the object to be welded , but appears between the tip electrode with core gas flowing around it . Plasma welding turned out better than tungsten because arc welding flame appears more stable electricity with a smaller diameter so that the heat is more concentrated . Welding process can run faster , besides that tungsten was never touched objects welded .
Ultrasonic Welding
Early 1960 was marked by the discovery of welding that uses high -frequency sound ( Ultrasonic Welding ) . It also uses an electric welding process works , there is no power on the object being welded , the heat generated is solely the result of the process and it is only to help in the process of unification of the object being welded . The voice that used ranges from 10,000 to 175,000 Hz , the sound vibrations are channeled through sosotrode mounted on a welded object . Then pressure is applied to the object being welded during the process . The advantages of this process is suitable for thin objects and not affected the type of material which you connect . Not wearing thermal energy as the primary energy is its own advantages in certain materials and thin , only less successful for the thickness of the welded objects above 2.5 mm x 2 .
Laser Welding
In 1955 the physicists managed to find a laser beam , is simply the light being produced at a particular wavelength and parallel , then enlarged , the beam will be focused next . The heat generated at the focal point is very high . By 1970 , the laser was implemented on a pedestal , as the laser beam can be set accurately so that laser welding is very appropriate for special equipment . Laser welding can be used to weld objects with a thickness of 0.13 mm to 29 mm at a shear rate range of 21 mm / sec to 1.2 mm / sec . Issues arising at the base of laser welding as well as electrons , estrangement welded very small objects between 0.03 to 0.15 .