A WELDABILITY STUDY OF STEEL OF STRENGTH CLASS X100

摘要

The effect of welded joint heat-affected zone (HAZ) cooling rate on structure, mechanical properties and brittle failure resistance of pipe steels of strength class X100 is studied by simulating welding thermal cycles in a Gleeble-3180 test unit. These properties are compared with results obtained with pipe welding, and good correlation of data obtained in a laboratory and for an actual pipe is demonstrated. It is also shown that the method for simulating thermal cycles makes it possible to evaluate properties of the heat-affected zone without associated processing factors during actual pipe welding. Research results make it possible to establish the range of HAZ cooling rates providing preparation of the required values of longitudinal weld properties for pipe of considerable diameter made from steel of strength class X100.