Elasticity is a property of material, which is manifested as reversible deformation under applied load. This reversible or elastic deformation is through stretching of inter-atomic bonds and therefore, there is an associated volume change with this type of deformation. Every material resists its deformation by the load applied onto it. In elastic deformation regime this resistance is measured by modulus of elasticity.
Thus modulus of elasticity is a measure of resistance of a material against reversible or elastic deformation. Depending upon mode of loading tensile, shear etc. there are different modulus of elasticity like Youngs modulus of elasticity (in tensile loading), Shear Modulus of elasticity (in shear loading) etc. Youngs modulus of elasticity is a very important property of a material. This is a measure of stiffness of the material against tensile loading.
It is an important design parameter for structural materials. Its value depends on the nature of inter-atomic bonding and is insensitive to the microstructure of the material. Ceramics have very high value of Youngs modulus of elasticity followed by metals and therefore, deflect very less under applied load; while wood and polymers have small value of Youngs modulus of elasticity and accordingly deflect more under applied load as compared to metals and ceramics under identical loading condition.
Another different kind of material with high value of Youngs modulus of elasticity is gaining popularity. These are composite materials and are synthesized by incorporating high modulus material ceramic whiskers in low modulus matrix like metallic or polymeric materials. In this experiment Youngs modulus of elasticity of two different kinds of timber (Parana Pine and Mahogany) and two different kinds of metallic alloys (60/40 brass and 0. 3% C steel) have been determined experimentally and the same is reported in this paper.