What is the principle of welding

Historical development of welding

Nowadays, welding is used everywhere to create connections that accompany our everyday lives. It has become indispensable. But how did it actually begin and how did mankind come up with the idea of ​​combining materials with one another through heat?

In this article, we would like to take a look back at how mankind discovered welding as a technology and which stages of development were gradually found or developed.

How it all started ...

It has been thousands of years since mankind first used the better ductility of metals under the action of heat. Historical finds in the kingdoms of the Sumerians and Hittites show that as early as 4000 BC Around the 8th century BC the technique of soldering was used to permanently connect gold, silver or copper. Brazing is probably the oldest thermal connection technology for metals, which is quite similar to the principle of welding.

Welding in the strict sense of the word is a little younger and can be traced back to ancient Egypt around 2700 BC. Can be traced back to BC. At that time they were used Fire welding technologyto connect copper pipes to water supply. The same technique was used to make jewelry from gold in a similar period of time. Further finds show that in the 15th century BC In Asia Minor, welding has already been carried out.

At that time, welding was used as a pure joining technique for metals with great durability. It was a means to an end. In the later course of time, the welding techniques were also transferred to other areas, for example for the production of tools or for decorating metallic objects with metal jewelry. With the transition from the Bronze Age to the Iron Age in Europe, iron was increasingly processed.

Technological peaks of development

This is considered the archetype of welding Fire weldingwhich was carried out with a high temperature and a large application of force in the form of hammer blows. This remained the only welding technology for millennia. The name "welding" comes from the fact that the surface of the metal apparently begins to "sweat" under the heat.

With the development of the electrifying machine in 1663 by Otto von Guericke was the cornerstone for electrical welds placed. In 1766 there were attempts by Johan Carl Wilcke, who welded two flint balls using a capacitor discharge, whereby a capacitor works similarly to a battery.

The decisive advances for successful Resistance welds Ultimately brought the Englishman Elihu Thomson in 1877.

The discovery of acetylene by Edmund Davy in 1836 made it possible to generate significantly hotter flames than with the previously known oxygen-hydrogen mixtures. Shortly thereafter, the Oxy-fuel welding or Gas fusion welding applied, which is still carried out occasionally today.

With a patent applied for in 1885, the Russian Nikolai Nikolaijewitsch Bernados is considered to be the inventor of the Arc welding with an arc between two carbon electrodes. A patent for arc welding, which was granted to an Englishman in 1849, has no practical application.

The process was perfected in 1907 by Oscar Kjellberg, who covered the electrodes and thus protected the weld seam from oxidation. The basic form of MMA welding, which is still widely used today, was invented.

Modern welding processes

As a further development of arc welding with carbon electrodes, Russel Meredith invented it in 1946 TIG welding, with a tungsten electrode and helium as a protective gas. TIG welding is still considered to be one of the standard processes for manual and fully automatic welding.

In 1948, just two years later, it was MIG welding which is mainly used for non-ferrous metals today.

This followed in 1951 Plasma welding, in the same period that Electroslag welding and in 1953 that MAG welding. The latter forms the counterpart to MIG welding and is used for ferrous metals.

The advantages of electric welding processes should replace gas fusion welding in record time. Other state-of-the-art welding processes followed in 1957 with the Ultrasonic welding and in 1961 with the Laser welding. These techniques minimize the distortion of the workpieces due to the low generation of heat.

The goal of such new developments has always been to carry out ever cleaner welds with less heat input. The techniques developed in 2005 Cold metal transfer and Cold Metal Arc achieve exactly these goals with a pulsed welding current. In addition, the control of the processes always had to be improved in order to make the welding processes usable in the industry with the welding robots manufactured from the 60s.

In general, one can say that the development of welding techniques has made bigger strides in the last 50 years than in the previous 5000 years. National and international associations work every day to improve existing welding techniques and develop new methods. In welding, as in many other areas, the end of technological development is still a long way off.