Question

explantion of stress-strain curve

Answer 1

It is unique for each material and is found by recording the amount ofdeformation (strain) at distinct intervals of tensile or compressive loading (stress). ... Thus, a point defining true stress-strain curve is displaced upwards and to the left to define the equivalent engineeringstress-strain curve.

Answer 2

Stress-strain graph : It's a graph which represents stress value against strain value of the given material ,when the material is subjected to increasing pull.

there are mainly six points in the graph.

proportional limit: it is the point upto which hookes law is applicable ie., stress is directly proportional to strain.
Elastic limit: there is always the limiting value of load upto which strain totally disappear on removal of load
material posses elastic nature and properties till elastic limit.
upto this point material obtains its original configuration on removing load.
Yeild point: The stress beyond which material becomes plastic.
Load at which permanent deformation of material starts.
○Ducticle point: beyond this point neck forms where the local cross sectional area becomes significantly smaller than original
material acquires plastic nature .
•Ultimate point: The point at upto which material can withstand maximum load and ultimate strength with maximum elongation .
large deformation possible before failure.
•Point of rupture: the stress which makes the material failure or break.