YERZLEY RESILIENCE– One test method is the Bayshore Resilience method. It calls for the dropping of a weighted ball from a specified height onto a given material sample. The rebound height of the ball is then measured and used to determine how resilient the material is to the stress. The result is an indicator of hysteretic energy loss.
Rebound resilience is the relationship or ratio between the returned energy and impact energy between a force, like a dropped hammer, and the sample specimen.
YIELD POINT– In materials science and engineering, the yield point is the point on a stress-strain curve that indicates the limit of elastic behaviour and the beginning of plastic behaviour. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed.
The yield point of a material occurs when the material transitions from elastic behaviour – where removing the applied load will return the material to its original shape – to plastic behaviour, where deformation is permanent.
If the upper yield point is exceeded, the plastic or permanent deformation begins; in tensile testing the specimen is irreversibly elongated.
YOUNGS’ MODULUS– Young’s modulus of elasticity is defined as the ratio of normal stress to the longitudinal strain within the elastic limit. 2. Bulk modulus of elasticity is defined as the ratio of normal stress to the volumetric strain within the elastic limit.
Young’s modulus, also referred to as elastic modulus, tensile modulus, or modulus of elasticity in tension is the ratio of stress-to-strain and is equal to the slope of a stress–strain diagram for the material.
Young’s Modulus of isotropic materials remains constant at all times. For e.g Metals, glass, polymers etc.