Accuracy assessment of formulas for cooling time (t8/5) calculation during the welding of carbon steels

Abstract

During welding and weldability assessment of certain material, very important parameter is cooling time in certain temperature range (the most important is range from 800 to 500ºC). In that range all transformations in material has to be done so that range (time t8/5) is the most critical one. Based on cooling time, and appropriate material properties, one can pre-dict characteristics of welded joint and heat affected zone. There is many ways to deter-mine cooling time but today, there is an increase of use of analytical and empirical formu-las. The aim of this paper is to point out the accuracy of that formulas regarding to experimental results (measuring with thermocouples). Analysis is based on testing on welding of samples made of carbon steels. In case if analytical and empirical formulas give satisfying results, they can be used to replace expensive experiments.