Fracture resistance of palm kernel seed to compressive loading.

Abstract

Quasi-static compression tests were carried out on treated single palm kernel seeds to study the effects of temperature, moisture content and loading position on the rupture force, deformation and toughness of the kernels. The levels of moisture content and temperature considered were 5, 7 and 10% w.b and 70, 90 and 110°C each at the horizontal and vertical loading position. Twenty palm kernel seeds were tested at each moisture and temperature level in both horizontal and vertical loading positions making a total of 480 kernels that were individually measured and tested. The average compressive force required to rupture a palm kernel seed under compressive loading decreased as the moisture content of the seed increased from 7 to 10% (wb), while the corresponding deformation increased from 1.18 to 1.43 mm but decreases from 1.18 to 1.03 mm as the temperature increases. Maximum toughness occurred at 7% moisture content and 70°C temperature respectively, indicating the optimum moisture content and temperature for absorbing compressive energy. The value of toughness is an important indicator of the ability of the palm kernel to resist mechanical damage during loading. The loading position has significant effect on the rupture force and should be considered when palm kernel seeds are being loaded. Key words: Resistance, compression loading, rupture, palm kernel, determination, toughness.