SELECTED MECHANICAL PROPERTIES OF BAMBARA GROUNDNUT SEEDS UNDER COMPRESSIVE LOADING

Knowledge of mechanical properties of agricultural materials is useful in the development of equipment for processing and handling them.Selected mechanical propertiesnamely rupture force, maximum deformation at rupture point, hardness and toughness of cream and light brown varieties of Bambara groundnut (BGN) seeds were determined at four moisture levels (5, 15, 25 and 35% dry basis) under compressive loading alongaxial and longitudinal orientations.Rupture force, deformation, hardness and toughness of BGN seedswere within the ranges 45.58-438.55 N, 0.31-5.71 mm,14.61-448.55 Nmm-1 and0.01-1.02J, respectively. Rupture force, deformation and toughnessof the seeds had interplay of increasing and deceasing trends while hardness decreased consistently as moisture content increased from 5% to 35%.The cream variety withstood higher rupture force and deformed more without failure than the light brown variety within moisture content range of 5-25% along both loading orientations.Bothvarieties demonstrated greater hardness when loaded along the longitudinal orientations than the axially loaded samples. All the investigatedproperties were dependent on moisture content andorientationof loading. Predictive mathematical models forestimating the investigated properties at different moisture contents with reasonable accuracy were also established in this study