Fundição em areia verde da carcaça da caixa de direção de um veículo mini baja

Abstract

The Baja SAE is an Collegiate Design Series competition run by the Society of Automotive Engineers International (SAE International), students must fuction as a team that represent the higher education institution to develop an off road vehicle. Improvements in prototype design are critical for team performance to improve each year. Therefore, one of the goals of the BAJA UEA team is to reduce the cost of the steering system. The possibility of manufacturing the steering system frame through green sand casting was raised, a low-cost process with accessible materials within the university structure. To carry out the casting project, the geometry of the part was analyzed in the molding study, then the model was dimensioned with machining allowances, rake angles and allowance for the part's solidification shrinkage. Then, the riser was dimensioned based on the thermal and volumetric requirements. The metallic alloy in this work is aluminum, a material that is highly oxidizable in the liquid state and, therefore, a depressurized channel system was used to avoid turbulence in the filling of the liquid metal in the mold. During the tests, it was possible to determine that the main parameters for the casting are: sand moisture, casting temperature and number of gas outlets. The results obtained were promising, considering that it was possible to manufacture a part that met the project's requirements without presenting defects that compromised the part's functionality, reducing the team's machining and raw material costs for the manufacture of the frame by up to 40% of the steering system.