Analysis of Mechanical and Micro-Structural Properties of Shaft Tips Manufactured in ABNT 1045 Steel Applied in Transportation Ore Fractured Early

This paper aims is the study of shaft tips applied in ore transportation that are subjected to continuous torsional stresses, and which rupture early. This component consists of an ABNT 1045 steel shaft, where an ABNT 1020 steel flange is welded by the MIG/MAG (GMAW) process, both fixed, in addition to welding, by ABNT 1020 steel latches welded to the flange and shaft. The methodology is based on fracture analysis of the material and application of thermal treatments at different temperatures in order to reduce the incidence of early fracture. The results showed that the thermal treatment at 300oC for 4 hours was the most efficient in all regions, giving the shaft an increase of tenacity, without losing its mechanical resistance and hardness, indispensable properties to the shafts taking into account its characteristics operation.