The investigation of torsional behaviour of AISI 4340/AISI 420 steel couple joined with friction welding method

The need to use different materials in combination emerged with the advancing technology today. The most appropriate method is welded joints joining of two different alloy steel. In the aftermath of the welding process, the characteristics of the source region, is different from the combined properties of steel has revealed significant problems. For this reason, different composition materials in bonding a smelting event absent or is limited, much less resources free from defects and weld minimum internal stresses have reasons, solid-state welding processes have been used. Fusion welding method is a method open to the source of the error and the macro-level of internal stresses during cooling of the major drawbacks of this method is to occur, which reduces the strength of the source. For this reason, different composition materials in bonding a smelting event absent or is limited, much less resources free from defects and weld minimum internal stresses have reasons, solid-state welding processes have been used. In this study, with widespread use in the market with AISI 4340 steel fusion welding breeding methods that combine the power of AISI 420 martensitic stainless steel is combined with different speeds, the friction welding method. The resulting structures formed in the intersection of these welded joints made metallographic evaluation, such as tensile and torsion tests aimed to investigate the mechanical behavior. As a result of studies determined optimum rotational speed and the rotational speed has been found best torsional strength. In the first section of this study, it was made introduction to the subject. In the second section, the place and importance in the literature of the subject were mentioned. In the third section, general informations were given about friction welding method, stainless steels, tempered steels, mechanical tests and torsion test. In the fouth section, experimental studying method was examined. In the fifth section, the results of the experimental studying were examined and their comments were writen. In the sixth section, general results and propasals were given.