1.1 Historical Background
Until very recently, the only method available to join metals was by forge welding, which requires two
pieces of metal to be heated and then pressed or hammered together to develop a metallurgical bond
between the two. Modern welding technology can trace its origins to the first half of the nineteenth
century, when advances in electrical technology such as the production of an arc between two carbon
electrodes and the invention of the electric generator took place. By the end of the nineteenth century,
these advances had led to the development of three welding processes:
- arc welding
- resistance welding
- oxy-acetylene welding