|Bowditch, William A. Welding Technology Fundamentals. Tinley Park: The Goodheart-Willcox Company, Inc. 1997: 269.||"Ionized gas or plasma is extremely hot — temperatures as high as 43,000 °F (24,000 °C) have been reached. The plasma arc is an excellent heat source for welding or cutting"||24,000 °C|
|Pierre-Jean Cunat.Chromium in Stainless Steel Welding Fumes. The Chromium File, 17 June 2003.||"In the electric arc, the temperature is very high(of the order of 6,000-8,000 °C for the GTAW, GMAW, FCAW and SAW processes, and up to 10,000 20,000 °C for the PAW process) and well above the boiling point of the base and filler materials…."||6,000-8,000 °C|
|Welds [pdf]. The University of Tennessee at Martin, 6 June 2003||"Electric current flowing through high resistance air gap generates an intense arc with temperatures ranging from 6,000 to 10,000 °F."||3,000-6,000 °C|
|Cary, B. Howard. Modern Welding Technology. Upper Saddle River: Prentice Hall, 1998: 466, 108.||"The electric arc has a temperature of from 5000 to 20,000 °C"||5000-20,000° C|
|"The plasma operates at a very high temperature, approximately 6,000 °C (10,000 °F)"||6,000 °C|
Welding is the most economical and efficient way to join metals permanently. It is the only way of joining two or more pieces of metal to make them act as a single piece. Metal inert gas (MIG), also known as gas metal arc welding (GMAW), is the most commonly used automatic welding process for steel and aluminum materials due to its welding speed and ease of use. MIG welding is a welding process in which metals are joined by heating them with a welding arc between the base metal and a continuous consumable electrode. Shielding gases such as argon and carbon dioxide are used to prevent the atmosphere from contaminating the welding arc and molten base metal. One of the main functions of the arc is to produce heat. The heat of the arc melts the surface of the base metal and the end of the electrode. The electric arc has a temperature that ranges from 3,000 to 20,000 °C. Welding fumes are complex mixtures of particles and ionized gases. The major source of these fumes is the plasma, which is located within the consumable electrode. The plasma is an excellent heat source for welding because it works well at extremely high temperatures such as 6,000 °C, including temperatures as high as 24,000 °C.
There are many advantages that outweigh the disadvantages in using MIG welding. Firstly, a continuous electrode is used so that longer welds can be made without stopping to change electrodes that may contribute to weld defects. Secondly, welding speeds are faster and no slag is produced. Therefore, more of the electrode becomes part of the weld. Lastly, the amount of fumes and skill required is much lower than with most other types of welding.
Tungsten inert gas welding (TIG) is a welding process in which an arc is struck between a tungsten electrode and the base metal. The tungsten electrode is a monconsumable electrode because it does not melt and become part of the weld. TIG welding functions similarly to MIG welding in that it uses a shielding gas to disperse the surrounding atmosphere. However, the shielding gas in the TIG process is helium. TIG welding can be used to make welds of great strength and quality in thin, light, and dissimilar materials.
Esther Dorzin -- 2003