Examination of microstructure and mechanical properties of structural steel profiles produced by two di̇fferent methods

Steel pipes and profiles are materials that are widely used due to their suitability for mass production with economical methods. In this study, longitudinally welded structural steel profiles produced from hot-rolled structural steel sheets using two different production methods and high frequency induction welding method were examined. Mechanical properties of manufactured structural tubes are examined by conducting destructive and nondestructive test methods.Tube expanding test (TS EN ISO 8493), hardness test and tensile test (TS 138 EN 10002-1) methods are applied to determined mechanical properties.On the other hand micro structural properties of tubes that manufactured by two different methods. The tensile test results of the produced profiles from welded and unwelded areas were evaluated and it was checked whether there were any differences. It was determined which of the tensile test results from unwelded areas of the samples produced with different process settings with two different methods were close to the raw material value. In the study, hardness measurements were made to see the effect of the two different methods on the profile bending areas and it was checked whether the criteria required by the standard were met with the mouth expansion test. The raw material amounts and mold setting times used in the production of the same profile with two different methods were also examined. As a result of these studies, two different production methods were compared and it was determined that the best production method used in the production of structural steel profiles was the new method of direct profile production with flexible cold forming.