This Presentation contains how a ESCR (Environmental stress cracking resistance) can be tested.

1. Environmental stress
cracking resistance
Prepared by
Sivaprakash. S
Department of Polymer Technology
Kamaraj college of Engineering and Technology
+91 99407 33520

2. Introduction
 Environmental Stress Cracking Resistance is
one of the most common cause of
unexpected brittle failure of thermoplastic
(especially amorphous) polymers known at
present.
 ESC may account for around 15 - 30% of all
plastic component failures in service.
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3. Predicting Environmental Stress
Cracking Resistance
 The rate of esc is dependent on many factors
including the polymer`s chemical makeup,
bonding, crystalinity, surface roughness,
molecular weight, residual stress.
 It also depends on the liquid reagent`s
chemical nature and concentration, the
temperature of the system and the strain
rate.
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4. Environmental Stress Cracking
Resistance Testing Machine
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5. Top View of ESCR5

6. ESCR sample holder and test
tube
Sample
After clamping
Sample
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7. Procedure
 The sample of 1.5 X 4 cm is taken.
 The sample is clamped in the sample holder. (ten samples
per holder)
 Then it is placed into the boiling tube.
 The tube is filled with detergent solution.
 Then it is closed with cork.
 Then it is placed in the instrument.
 The temperature is turned on.
 The test is carried out for half an hour.
 Then the samples are taken out.
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8. What to do after the test?
 The samples are carefully taken out.
 The samples are examined for cracks on the
surface.
 The results are given by defects per 10
samples.
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9. Significance
 The test is carried out to know about the
withstanding of the material to the contact
of the environment.
 This test tells about the character of the
sample to the environment.
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