Welding of Stainless Steel

7/31/2019 Welding of Stainless Steel

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Welding of Stainless Steels


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When compared with common

carbon steels, the austeniticstainless steels exhibit the

following differences


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Electrical Resistance is about six timesgreater

Melting point is about 93 degree c. lower

Thermal Conductivity is about 50% lower

Thermal expansion is about 50% greater


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The greater expansion of stainlesssteel increases the tendency forwarpage and distortion and mayproduce a higher incidence of weldcracking under restraint conditions,

especially in the higher alloy types


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When austenitic stainless steels areheated within the temp range of 427 to

870 degree centigrade, or cooled slowlythrough that range carbon isprecipitated from solid solution mainlyat the grain boundaries, where it unitesintergranularly with chromium to formchromium rich carbide


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The formation of these carbides

effectively eliminates much of thechromium (from adjacent areas) whichwould otherwise be available to formthe protective chromium oxide.


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It is natural that the areas impoverishedin chromium have a lower corrosionresistance and under corrosive

conditions this results in a localizedintergranular attack, the severity ofwhich depends on the time and temp of

exposure, as well as the compositionand prior heat treatment of the steel


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Welding of Stainless Steel

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