The purpose of this lab was to test the mechanical properties of various nut and sea-shell structures, and their materials. For compression, we determined the ultimate strength, toughness, elasticity, and Young’ modulus for the almond, brazil nut, pecan, walnut, and hazelnut shells using a material testing apparatus. Properties were recorded in both intact and fragmented forms. This procedure allows us to see if the intact shell properties directly reflect the ultimate strength, toughness, elasticity, and Young’ modulus of the materials that make up the shell or if the structure shell itself plays a bigger role. Methods Before compressed, we recorded length, width, and thickness for each type of nut to find the cross-sectional area. The …show more content…
This is because the Brazil nut contains the strongest shell so it is more difficult to break. Yet, the elasticity is the greatest in the pecan nut, this could be due to the orientation of the nut shell being able to bend more before it breaks at a larger point. The intact Hazelnut is the greatest in strength, toughness, and elasticity, but the Young’s module is greater in the fragmented form meaning the structure of the shell plays a greater role in the make-up of the materials. In 40% of the cases, the intact shell has a higher threshold than the fragment, this means structure plays an important part in the mechanics, just as much as the material itself. From an ecological setting, this could mean that the Brazil nut trees could withstand greater winds or harsher predator settings due to the shells strength. Figure 1 reveals that stress and strain are positively correlated, where an increase in one category causes and increase in the other. The Young’s modulus was calculated with the mean data rather than the max because it represents the data in a more wholesome way. The results do not include the walnut fragmented data due to user error when testing for