Efeitos de tratamentos térmicos na propriedade de dureza do aço SAE 4340 na soldagem pelos processos FCAW e Laser: uma revisão

Abstract

The steel SAE 4340 is a steel for beneficiation with high hardenability, connected to the chromium-nickel-molybdenum, used in the manufacturing of different mechanical components, including thick sections, when a combination of average mechanical resistance and fracture resistance is desired. It also has high resistance to fatigue. This steel is used in components for mechanical systems, primarily structural, where you need-if a homogeneity in hardness along the cross-section in large or small sections. Its main applications are: Shafts, gears, planetary gears, columns, sleeves, and cylinders. The reason of this work is to show the effects of heat treatments on the variation of the hardness of the parts subject to the processes of welding via flux-cored wire and laser. It was concluded that the treatments of pre and post heating and tempering, have contributed to the improvement of toughness, a reduction in the hardness of the ZF and MB, and at the strain relief location.