To predict the cracking of rice grains during drying and subsequent storage, information must be available about mechanical strength and Young's modulus. In this work, experimental results are presented on Young's modulus, the tensile strength and the compressive strength of rice grains as a function of strain rate, and moisture content at 20 0C. Young's modulus and compressive strength decrease with decreasing strain rate and reach a constant value at a strain rate of 7.1 × 10{sup}(-3) min{sup}(-1). This value is higher than the local strain rates during drying at 200 ℃, so that during the modeling of the drying process the mechanical properties can be assumed to be rate-independent. At moisture contents of 8.87 (w.b.) and below, the values of Young's modulus and the tensile and compressive strength are not significantly different from each other (α = 5), while at moisture contents of 8.87 (w.b.) and higher; they decline with moisture content.
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