2. Determining instantaneous mechanical behavior

Experimental study of instantaneous behavior up to failure is most often carried out by applying constant-velocity deformation to a specimen, for different types of loading such as tension, bending, compression or shear, and recording the force-deformation curve. These four types of behavior can be studied using the same experimental unit, called a tensile testing machine or dynamometer, as described in standard NF EN ISO 5893, with only the specimen fixture modified to suit each case. For high speeds, the tests are referred to as shock-traction or shock-flexion tests, and the equipment used may be of a special design (e.g. pendulum-molders, see § 2.5.1