Heat Treatment and Phase Transformation ,Testing of Materials with Lab Report Presentation

1. Heat Treatment and Phase Transformation &
Testing of Materials
Lab Report Presentation

2. Aim:
• To observe the Microstructure of the given sample
• To apply heat treatment process (Normalizing) on it and observe the changes because of it
• To do the hardness test on sample before and after the heat treatment process
Apparatus:
• Sample Specimen
• Sand paper (Grain per unit area 80,150,180, 220, 400, 600)
• Disc polisher machine for cloth polishing
• Abrasive Agent ( Al2O3)
• Etchant
• Drier
• Microscope
• Furnace

3. Procedure:
1. Specimen is cut in required shape by using
Abrasive cutter machine.
2. Then polish the specimen again by using sand
papers (80,150,180, 220, 400, 600, grade),
3. Fine Polishing (Cloth Polishing) is done on a
Disc Polisher with speed of 220-300 rpm
Suspension of fine Alumina powder(Al2O3)
used as a polishing medium.
4. A Scratch free surface is obtained after fine
polishing for sufficient period (15minutes).
5. After fine polishing specimen is thoroughly
washed with water and dried.
6. Itching was done from nital solution( 98%cc
Ethyl Alcohol and 2%cc Nitric Acid). Very mild
etching was done as per guided by lab
attendants.
7. Observed the microstructure in microscope.

4. Precautions:
1. Grinding should be done on the emery papers only in one direction.
2. While polishing the specimen uniform pressure should be exerted on the specimen
3. While going to the next grade of emery papers, the specimen has to be rotated
through 90 degrees.
4.After etching the specimen should be washed away within a few seconds .
Observation:
100x 200x 500x
Microstructure of the given sample

5. Hardness Test Values before Heat Treatment
Load = 1KN
Load Time = 10s
No. of Repetitions = 4
Avg micro hardness value = 313

6. Grain Size Report

8. Multiphase Analysis Report

10. HEAT TREATMENT PROCESSES
• In general, heat treatment can be defined as an operation, or the
combination of operations that involve heating and cooling of a
metal in solid phase to obtain certain required properties.
• The ferrous materials can be heated to above transformation
temperature and can be heat – treated to obtain different structure.
• The different heat treatment processes are based on heating the
material to certain temperature and employing different cooling
rates.
• In this process, heating temperature and rate of cooling adopted
plays an important role.

11. Apparatus Required:-
• Cast Iron sample
• Muffle Furnace
• Crucibles and tongs
Procedure:-
• Kept the Specimen inside the furnace
and close the door.
• Switch on the furnace, set the
temperature control knob to given
temperature.(930^ C)
• The specimen in the furnace allowed
heat for 1 hr 30 minutes.
• The specimen is taken out and kept in
normal room air and temperature for 30
minutes
• Then repeat Fine Polishing experiment
& measure the Rockwell hardness values
further repeated steps for getting
microstructure.
Normalizing of Grey Cast Iron.
A video of the
furnace process

12. Observations:-
1. Black Carbon Flakes are disappeared and segregated in few places
2. Whitish structures are in abundance.
Microstructure, After Normalizing
100x 200x 500x

13. Hardness Test Values after Normalizing
Load= 1KN
Load Time = 10 sec
No. of Repetitions = 4
Average Hardness value = 197

14. -----THANK YOU-----
Before Heat Treatment After Heat Treatment
Hardness Value = 313 Hardness Value = 197
Abundant Graphite flakes in the sample Very few or no graphite flakes at all