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RE: [MW:4977] Carbone Equ.

Dear Tamer,

 

Carbon equivalents (CE) seek to account for the sum of the effects of the several elements present in steel on its hardenability, and thus the susceptibility of a weld to cracking. It calculates the steel’s potential to form martensite or strengthening carbides based upon the steel chemistry. The higher the carbon equivalent, the harder the steel becomes and more prone to cracking upon cooling. Steels with carbon equivalents (CE) less than 0.4 percent are typically easy to weld and welded without special welding methods.

 

Different codes/ Standards/ literature specify different formulae for calculating CE. Most widely followed is AWS D1.1 which is as follows

 

CE = C + (Mn + Si)/6 + (Cr + Mo + V)/5 + (Ni+Cu)/15

 

However, Hardnability can be also controlled by pre-heating and thereby reducing the cooling rate and preventing the formation of martensite

Regards,
Rupesh A. Jambhale
Inspection Department,
Oil, Gas & Petrochemical Division,
Mott MacDonalds Consultants ( I) Pvt Ltd., Mumbai



-----Original Message-----
From: materials-welding@googlegroups.com [mailto:materials-welding@googlegroups.com] On Behalf Of tamer said
Sent: 28 April 2010 13:53
To: materials-welding@googlegroups.com
Subject: [MW:4974] Carbone Equ.

Why CE calcuations is essential ???
is it for corrosin or weldiability.
thx


     


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