The history of joining metals goes back several millennia, with the first examples of welding from the Bronze Age and the Iron Age in Europe and the Middle East. The ancient Greek historian Herodotus says in The Histories of the 5th century BC that Glaucus of Chios "was the man who single-handedly invented iron-welding." Welding was implemented in the construction of the iron pillar in Delhi, India, erected about 310 AD and weighing 5.4 metric tons.
The Middle Ages brought progression in forge welding, in which blacksmiths pounded heated metal repeatedly until bonding occurred. In 1540, Vannoccio Biringuccio published De la pirotechnia, which includes descriptions of the forging tactic. Renaissance craftsmen were talented in the process, and the industry continued to grow during the following centuries.
In 1802, Russian scientist Vasily Petrov found the electric arc and subsequently proposed its possible practical applications, including welding. In 1881–82 a Russian inventor Nikolai Benardos developed the earliest electric arc welding method known as carbon arc welding, using carbon electrodes. The advances in arc welding evolved with the invention of metal electrodes in the late 1800s by a Russian, Nikolai Slavyanov (1888), and an American, C. L. Coffin (1890). Around 1900, A. P. Strohmenger put out a coated metal electrode in Britain, which gave a more stable arc. In 1905 Russian scientist Vladimir Mitkevich proposed the implementation of three-phase electric arc for welding. In 1919, alternating current welding was invented by C. J. Holslag but did not become in demand for another decade.
Resistance welding was also created during the final decades of the 19th century, with the first patents going to Elihu Thomson in 1885, who produced further advances over the next 15 years. Thermite welding was invented in 1893, and around that time another process, oxyfuel welding, became well in place. Acetylene was discovered in 1836 by Edmund Davy, but its use was not practical in welding until about 1900, when a suitable blowtorch was created. At first, oxyfuel welding was one of the more in demand welding methods due to its portability and relatively low cost. As the 20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding, as metal coverings (known as flux) for the electrode that stabilize the arc and shield the base material from impurities continued to be created.
World War I caused a major surge in the implementation of welding processes, with the various military powers attempting to determine which of the several new welding processes would be best. The British primarily implemented arc welding, even constructing a ship, the Fulagar, with an entirely welded hull. Arc welding was first applied to aircraft during the war as well, as some German airplane fuselages were constructed using the tactic. Also noteworthy is the earliest welded road bridge in the world, designed by Stefan Bryla of the Warsaw University of Technology in 1927, and built across the river Sludwia Maurzyce near Lowicz, Poland in 1929.
During the 1920s, major advances were made in welding technology, including the bringing forward of automatic welding in 1920, in which electrode wire was fed continuously. Shielding gas became a subject getting much attention, as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems, and the solutions that created included the implementation of hydrogen, argon, and helium as welding atmospheres. During the next decade, further advances allowed for the welding of reactive metals like aluminum and magnesium. This in conjunction with developments in automatic welding, alternating current, and fluxes fed a major evolution of arc welding during the 1930s and then during World War II.
During the middle of the century, many new welding methods were created. 1930 saw the release of stud welding, which soon became in demand in shipbuilding and construction. Submerged arc welding was invented the same year and continues to be in demand today. In 1932 a Russian, Konstantin Khrenov successfully used the earliest underwater electric arc welding. Gas tungsten arc welding, after decades of advancement, was finally perfected in 1941, and gas metal arc welding followed in 1948, allowing for fast welding of non-ferrous materials but requiring expensive shielding gases. Shielded metal arc welding was created during the 1950s, using a flux-coated consumable electrode, and it quickly became the most popular metal arc welding process. In 1957, the flux-cored arc welding process debuted, in which the self-shielded wire electrode could be used with automatic equipment, resulting in greatly increased welding speeds, and that same year, plasma arc welding was created. Electroslag welding was brought forward in 1958, and it was followed by its cousin, electrogas welding, in 1961. In 1953 the Soviet scientist N. F. Kazakov proposed the diffusion bonding tactic.
Other recent advancements in welding include the 1958 breakthrough of electron beam welding, making deep and narrow welding possible through the concentrated heat source. Following the creation of the laser in 1960, laser beam welding debuted several decades later, and has proved to be especially useful in high-speed, automated welding. Electromagnetic pulse welding is industrially implemented since 1967. In 1991 friction stir welding was created in the UK and found high-quality applications all over the world. All of these four new processes continue to be quite expensive due the high cost of the essential equipment, and this has limited their applications.