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PERFORMANCE EVALUATION OF CUTTING TOOL MATERIALS

SATHISH KUMAR P M
FIRST YEAR M-TECH ( TOOL ENGG)
GOVT. TOOL ROOM AND TRAINING CENTRE
BANGALORE

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FRACTURE MECHANICS

ELASTIC BEHAVIOUR
When a material is being loaded in uni-axial tension, compression, or simple shear it will behave elastically until a critical value of normal stress or shear stress is reached and then it will behave plastically.

If the applied loads are relatively low, the crystal responds by simply stretching or compressing the distance between the atoms. The basic lattice unit does not change, and all of the atoms remain in their original position relative to one another.

Elastic deformation stretches atomic bonds in the material away from their equilibrium radius of separation of a bond, without applying enough energy to break the inter-atomic bonds.