STRESS -STRAI DIAGRAM

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→NAME:AADIL AHMAD RATHER→COURSE:B.TECH(MECH) III SEM→SEC.:A (A1)→ROLL NO.: 01(ONE)→TOPIC: STRESS STRAIN DIAGRAM FOR DUCTILE

MATERIALS→SUB.:SOM→SUBMITTED TO: MR. TAPASH SIR

STRESS-STRAIN DIAGRAM FOR DUCTILE MATERIALS

→ACCORDING TO HOOK"S LAW ,UP TO THE POINT, WHICH IS CALLED PROPORTIONAL LIMIT,THE STRESS IS DIRECTLY PROPORTIONAL TO STRAIN.

→BUT WHEN IN REAL LIFE WE SEE THAT WHENEVER LOAD IS INCREASED BEYOND THIS LIMIT THE MATERIAL TENDS TO FRACTURE. SO IN ORDER TO STUDY THIS , WE USE SSD.

→THE DUCTILE MATERIALS DONT BREAK EASILY BUT IT GOES THROUGH MANY STAGES & THEN ULTIMATELY IT BREAKS.

CONTD.....• WHEN A SPECIMEN IS SUBJECTED TO TENSILE

LOAD ,IT EXPERIENCES A FORCE WHICH TENDS TO BREAK IT. BUT THE STRESS OF BAR EQUILLIBRIUMS THIS FORCE TO SOME EXTENT..

• FIRST UPTO SOME VALUE THE STRESS MOVES LINEARLY WITH THE STRAIN. AND THE GRPH COMES TO BE A STRAIGHT LINE. THIS LIMIT IS CALLED PROPORTIONAL LIMIT (A).

• THEN WHEN STRESS INCREASES THE GRAPH REACHES TO B WHICH IS CALLED ELASTIC LIMIT OR MAX. STRESS POINT.

• THE POINT REACHES THEN TO C , WHICH IS CALLED UPPER YEILD POINT.

• AFTER THIS THE GRAPH REACHES TO POINT D CALLED AS LOWER YEILD POINT.

CONTD...• AFTER THE STRESS REACHES

ITS ULTIMATE POINT , THAT POINT ON THE GRAPH IS CALLED AS ULTIMATE STRESS POINT.

• AND AFTER THIS POINT THE SPECIMEN GETS FRACTURED ,AT POINT F

stress-strain diagram for ductile materials