The weldability of a material refers to its ability to be welded. Many metals and thermoplastics can be welded, but some are easier to weld than others. It greatly influences weld quality and is an important factor in choosing which welding process to use.
The weldability of
steels is inversely proportional to a property known as the hardenabilityof the steel, which measures the ease of forming martensiteduring heat treatment. The hardenability of steel depends on its chemical composition, with greater quantities of carbon and other alloying elements resulting in a higher hardenability and thus a lower weldability. In order to be able to judge alloys made up of many distinct materials, a measure known as the equivalent carbon contentis used to compare the relative weldabilities of different alloys by comparing their properties to a plain carbon steel. The effect on weldability of elements like chromiumand vanadium, while not as great as carbon, is more significant than that of copperand nickel, for example. As the equivalent carbon content rises, the weldability of the alloy decreases. inote|Lincoln Electric, 6.1-1 The disadvantage to using plain carbon and low-alloy steels is their lower strength—there is a trade-off between material strength and weldability. High strength, low-alloy steels were developed especially for welding applications during the 1970s, and these generally easy to weld materials have good strength, making them ideal for many welding applications. inote|Lincoln Electric, 6.1-14 - 6.1-19 Stainless steels, because of their high chromium content, tend to behave differently with respect to weldability than other steels. Austenitic grades of stainless steels tend to be the most weldable, but they are especially susceptible to distortion due to their high coefficient of thermal expansion. Some alloys of this type are prone to cracking and reduced corrosion resistance as well. Hot cracking is possible if the amount of ferrite in the weld is not controlled—to alleviate the problem, an electrode is used that deposits a weld metal containing a small amount of ferrite. Other types of stainless steels, such as ferritic and martensitic stainless steels, are not as easily welded, and must often be preheated and welded with special electrodes. inote|Lincoln Electric, 7.1-9 - 7.1-13
The weldability of
aluminiumalloys varies significantly, depending on the chemical composition of the alloy used. Aluminium alloys are susceptible to hot cracking, and to combat the problem, welders increase the welding speed to lower the heat input. Preheating reduces the temperature gradient across the weld zone and thus helps reduce hot cracking, but it can reduce the mechanical properties of the base material and should not be used when the base material is restrained. The design of the joint can be changed as well, and a more compatible filler alloy can be selected to decrease the likelihood of hot cracking. Aluminium alloys should also be cleaned prior to welding, with the goal of removing all oxides, oils, and loose particles from the surface to be welded. This is especially important because of an aluminium weld's susceptibility to porositydue to hydrogenand drossdue to oxygen. inote|Lincoln Electric, 9.1-1 - 9.1-6
*Lincoln Electric (1994). The Procedure Handbook of Arc Welding.
Cleveland: Lincoln Electric. ISBN 99949-25-82-2.
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Weldability — Weldability. См. Свариваемость. (Источник: «Металлы и сплавы. Справочник.» Под редакцией Ю.П. Солнцева; НПО Профессионал , НПО Мир и семья ; Санкт Петербург, 2003 г.) … Словарь металлургических терминов
weldability — ˌweldəˈbiləd.ē noun ( es) : the quality, state, or property of being weldable : the capacity to undergo welding the chief factors governing weldability of aluminum E.G.West tables on weldability of materials W.A.Stanley … Useful english dictionary
weldability — noun The ability of a metal or other material to be welded under specified conditions … Wiktionary
weldability — Смотри Свариваемость … Энциклопедический словарь по металлургии
weldability — weld·abil·i·ty … English syllables
Свариваемость — Weldability Свариваемость. Определенная или относительная мера способности материала свариваться при данных условиях. (Источник: «Металлы и сплавы. Справочник.» Под редакцией Ю.П. Солнцева; НПО Профессионал , НПО Мир и семья ; Санкт Петербург,… … Словарь металлургических терминов
Свариваемость — [weldability] способность материалов образовать неразъемное соединение при сварке посредством установления прочных химических связей при сохранении механических и физико химических свойств на уровне соединения материалов или при допустимом их… … Энциклопедический словарь по металлургии
СВАРИВАЕМОСТЬ — [weldability] способность материалов образовывать неразъемное соединение при сварке посредством установления прочных химических связей при сохранении механических и физико химических свойств на уровне соединений материалов или при допустимом их… … Металлургический словарь
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 (the weld puddle ) that cools to… … Wikipedia
Equivalent carbon content — The equivalent carbon content of a steel alloy refers to method of measuring the maximum hardness and the weldability of the alloy based on the chemical composition of the alloy. Higher concentrations of carbon and other alloying elements such as … Wikipedia