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Drop-Weight Tear Test is another way of determining fracture behavior of steel. The method owes its origins to Naval Research Laboratories tests for determining the NDT of steel, in 1950s.

The process involves use of a 4” wide full section steel plate with a sharp notch in the middle. The notch is made with a sharp chisel that has small cutting tip ground to a radius. The DWTT specimen is broken via three-point impact loading using a drop-weight or pendulum hammer that has a velocity of no less than 5 meters/Second (16 ft/s). The specimen is cooled in the bath to required temperature. The specimen is broken in one single blow.

In this method no attempt is made to measure the absorbed energy. Evaluation of broken surface is based on the texture of the fractured ends. The appraisal is made on the percentage of ductile shear facture.