Autogenous welding is a form of

welding Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Co ...

in which the filler material is either supplied by melting the base material or is of identical composition. The weld may be formed entirely by melting parts of the base metal, and no additional filler rod is used. There is some variation in the use of this term. Those bodies concerned with teaching the craft skill of welding tend to define it as using no filler rod, i.e. the technique is based purely on the base metal. Those concerned with the welded joint's

metallurgy Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the ...

may make no distinction between a filler rod and the base metal, provided that the final metallurgy is identical. Most welding processes may be either autogenous or use additional filler. Some are characteristically autogenous and avoid filler. Some

arc welding Arc welding is a welding process that is used to join metal to metal by using electricity to create enough heat to melt metal, and the melted metals, when cool, result in a joining of the metals. It is a type of welding that uses a welding power ...

processes, including such major process such as manual metal arc (stick) welding and MAGS (wire-feed) welding, cannot be used autogenously, as they rely on the consumption of a filler rod to provide the arc. Some processes are typically autogenous. These include some

gas welding Principle of burn cutting Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline or petrol, diesel, bio ...

processes such as lead burning (although fillers may optionally be used) and

oxy-acetylene welding Principle of burn cutting Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline or petrol, diesel, bio ...

in some positions, such as

seam welding Electric resistance welding (ERW) is a welding process in which metal parts in contact are permanently joined by heating them with an electric current, melting the metal at the joint. Electric resistance welding is widely used, for example, in manu ...

the edges of two overlapping sheets.

Resistance welding Electric resistance welding (ERW) is a welding process in which metal parts in contact are permanently joined by heating them with an electric current, melting the metal at the joint. Electric resistance welding is widely used, for example, in manu ...

, both

spot welding Spot welding (or resistance spot welding) is a type of electric resistance welding used to weld various sheet metal products, through a process in which contacting metal surface points are joined by the heat obtained from resistance to electric ...

and

, is inherently autogenous, as there is no convenient way to apply a filler.

Friction Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of t ...

and

laser welding A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of rad ...

have similar restrictions. Some alloys are prone to changing their composition when heated, particularly a loss of

zinc Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic tabl ...

from

brass Brass is an alloy of copper and zinc, in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic and chemical properties, but copper typically has the larger proportion, generally copper and zinc. I ...

by its evaporation as vapour. In these cases, an excess of 2–3% extra zinc may be provided in the filler rod to compensate. Silicon may also be used as an additive to reduce this loss. A few materials, such as the

HY-80 HY-80 is a high-tensile, high yield strength, low alloy steel. It was developed for use in naval applications, specifically the development of pressure hulls for the US nuclear submarine program and is still currently used in many naval applicati ...

series of high-strength steels, require a non-autogenous process to control their metallurgy. However, advanced processes, such as hybrid laser arc welding, have been used to achieve the same effect autogenously.

References

{{Reflist, refs= {{Cite book , title=The Welding, Brazing and Soldering of Copper and its Alloys , publisher= Copper Development Association , location=England , id=CDA Publication Nº47 , origyear=1952 , edition=4th , year=1956 , ref={{harvid, Welding, Brazing and Soldering of Copper and its Alloys, 1952 , page=29 {{Cite journal , last=Roepke, first=C , date=August 2009 , title=Hybrid Laser Arc Welding of HY-80 Steel , url=https://app.aws.org/wj/supplement/wj0809-159.pdf , journal=Supplement to Weld. J. , volume=88 , pages=159–167 Welding