Work Required to Cause Failure of Tablets in Diametral Compression

Drug Development and Industrial Pharmacy (Impact Factor: 2.1). 10/2008; 4(2):131-156. DOI: 10.3109/03639047809055644


Abstract During diametral compression testing load-displacement curves were obtained for tablets made from some direct compression agents, by continually monitoring the force applied to the tablet and the distance moved by the lower compression platten. The area under these curves, termed work of failure, was calculated by numerically integrating the applied force with respect to platten displacement. The resistance to breakage of the tablets was assessed by a semi-empirical multiple diametral impact test in which a tablet was subjected to repeated impact until failure occurred. Work of failure was related to the number of impacts required to cause failure and appears to be a better quantitative assessment of a tablet's mechanical properties than tensile strength.

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