The Paton Welding Journal, 2012, №08



2012 №08 (02)

2012 №08 (04)

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The Paton Welding Journal, 2012, #8, 11-16 pages  

MATHEMATICAL FORMULATION OF CARBON EQUIVALENT AS A CRITERION FOR EVALUATION OF STEEL WELDABILITY

V.A. KOSTIN

E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
 
 
Abstract
A new criterion is proposed for cold cracking susceptibility of HAZ metal of joints on hardenable steel, based on allowing for the kinetics of austenite decomposition and experimental determination of the incubation period of the start of martensite transformation. It is shown that this criterion can be mathematically reduced to the traditional parameter for assessment of such a weldability of hardenable steels - carbon equivalent. A mathematic dependence of the new criterion on value of carbon equivalent is proposed, which was verified experimentally.
 
 
Keywords: modelling, carbon equivalent, weldability, criteria, cold cracks, diagram of austenite decomposition, martеnsite, technological tests
 
 
Received:                08.05.12
Published:               28.08.12
 
 
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