Design of experiments to identify material properties

Uniaxial tensile tests were carried out to obtain the variation of the material properties from one aluminium extrusion to another as well as over the cross-section and along the extrusion. Tests were performed in tension and compression to evaluate the effect of loading, and the anisotropy was determined through uniaxial tensile tests in three different directions: 0°, i.e. the extrusion direction, 45° and 90°. The difference in strength between the three aluminium alloy AA6082-T6 extrusions was approximately 12%. Furthermore, the strength depends strongly on the orientation of the specimen relative to the extrusion axis. Highest strength was observed for the 90° direction while the 45° direction has least strength. The compressive strength was significantly higher than the tensile strength, while the variation of the strength over the cross-sections and along the extrusions was not prominent. Several experimental designs were investigated, and comparison of the results by analysis of variance and hypothesis testing was used to identify the best experimental design.