Effects of temperature and moisture content on the strength properties of African nutmeg (Monodora myristica)

The effects of temperature and moisture content of African nutmeg seedcoat was studied as it affects compressive force, deformation, failure stress, strain energy and modulus of elasticity (firmness). Quasi-Static compressive tests were conducted at Sample temperatures of 60^o, 100^o, 140^o, 180^o and 220°C. Similar tests were also performed at moisture content levels of 8.0, 11.2, 14.0, 17.4 and 28.7 percent (db) in an axial loading orientation. Investigations reveal that force needed to crack open the seedcoat decreased from 52.8N to 32.0N at temperatures of 60°C and 220°C respectively. A similar trend was also observed as compressive force decreased from 56.6N to 33.0N as moisture levels increased from 8.0 to 28.7 percent respectively. Deformation values were observed to increase from 0.64mm to 0.97mm for 60°C and 220^oc respectively. These values of deformation varied from 1.07mm to 1.54mm at moisture content levels of 8.0 to 28.7 percent respectively. Failure stress, strain energy and young's modulus all tended to decrease with an increase in temperature. Also as moisture content increases, failure stress and modulus of elasticity decreased. However, an increase in strain energy was observed from 0.0201N.mm to 0.0341N.mm for an increase in moisture from 8.0 to 28.7 percent respectively. Based on these findings important recommendations are made.