Stress Analysis in Automobile Components Using Reflexive Photoelasticity Technique

Abstract

The main objective of this work was to introduce Reflexive Photoelasticity Technique in qualifying automotive components at Fiat Automoveis S.A in Brazil. Actual stresses were determined in a simple geometry plate and also in nodes of a body shell of a passenger vehicle by using reflexive photoelasticity methodology. Initially, tests were performed in welded steel plates submitted to traction loads. These plates were previously coated with birrefringent plastic material. External loads were applied through hydraulic MTS actuators. Stress and strain distribution in welded points neighboring areas using reflexive polariscope were quantitative determined. Simultaneously, these stress and strains acting on the welded plate were determined using strain gauges. The results from both experimental techniques (photoelasticity and strain gauges) were compared with those obtained from a numerical model using finite element method. The results were correlated and analyzed. Finally, reflexive photoelasticity technique was used to determine the stresses in nodes of a body shell of a passenger vehicle. Through this analysis it was possible to determine critical points in the structure with peak stresses.