Welding is a fabrication process that joins materials, usually metals
or thermoplastics, by causing coalescence. This is often done by
melting the workpieces and adding a filler material to form a pool of
molten material that cools to become a strong joint, but sometimes
pressure is used in conjunction with heat, or by itself, to produce
the weld. Many different energy sources can be used for welding,
including oxy-acetylene gas, an electric arc, a laser, an electron
beam, friction, and ultrasound. While often an industrial process,
welding can be done in many different environments, including open
air, underwater and in space. Until the end of the 19th century, the
only welding process was forge welding, which blacksmiths had used for
centuries to join metals by heating and pounding them. Arc welding and
oxyfuel welding were among the first processes to develop during the
1800s. Welding technology advanced quickly during the early 20th
century as World War I and World War II drove the demand for reliable
and inexpensive joining methods. Following the wars, several modern
welding techniques were developed, including shielded metal arc
welding, gas metal arc welding, submerged arc welding and flux-cored
arc welding. Today, the science continues to advance, with robot
welding becoming more commonplace in industrial settings, and
researchers continuing to develop new welding methods.
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Today's selected anniversaries:
The Godiva procession in Coventry, England, began.
Johnstown Flood: A flood killed over 2200 people in Johnstown,
Pennsylvania, United States.
German and British navies clashed in the Battle of Jutland, the
largest naval battle of World War I.
Syria and Israel signed a disengagement agreement to resolve the Yom
The Trans-Alaska Pipeline System was completed.
Wikiquote of the day:
"When there are no more memories of heroes and martyrs, And when all
life and all the souls of men and women are discharged from any part
of the earth, Then only shall liberty or the idea of liberty be
discharged from that part of the earth, And the infidel come into full
possession." -- Walt Whitman in Leaves of Grass