Practical project Group 3
Amir Keyvan Edalat
Keivan Heydari
Mahdi Masoumi
1
SYS862-1/Autumn 2014
Outline
Overview of project
Experimental methods
Experimental results
Physical properties
Chemical properties
Metallography
 Grain boundary
 Microstructure
Conclusion
2
Overview of Project
Material identification
Material properties
Microstructure
Manufacturing method
Applications
3
Experimental Methods
Visual observation
Physical properties
Macro hardness
Chemical composition
 Energy dispersive X-ray spectroscopy (EDX)
X-ray fluorescence (XRF)
Microstructure
Optical microscope
Scanning electron microscope(SEM)
4
Visual Observation
Rectangular shape (75.7*43.7*19.1 mm)
 Side view
Code b4a2
 Surface view
Effect of spark
5
Physical Properties




Light gray color
Density = 7,75 gr/cm3
No damping of noise
Attracted by magnet
Ferro alloy
Steel
Not a %100 Austenitic Steel
6
Macro Hardness
Same hardness value in all direction
Top
Side
Height
33,6
33,4
32,6
33,5
33,5
34,9
32,9
32,8
33,2
Average
33,3
33,2
33,5
Standard deviation
0,309121
0,309121
0,974109
Hardness(HRC)
7
Chemical Composition
SEM – EDX
Confirms AISI P20 Steel
8
Chemical Composition
XRF analysis
The XRF result.
Si
Ni
Cu
Mo
V
Mn
Cr
1
0.1531
0.4316
0.1464
0.5077
0.1981
0.99
1.7965
2
0.1864
0.4409
0.1175
0.5122
0.1708
0.8857
1.8297
3
0.1616
0.4182
0.1532
0.5025
0.1459
1.0055
1.8177
Average
0.167033
0.430233
0.139033
0.507467
0.1716
0.9604
1.814633
Standard Deviation
0.014127
0.009317
0.015477
0.003963
0.021318
0.053199
0.013726
 Suggested material based on derived composition
 ASTM A681
 Grade AISI P20
 Conventional P20 does not have Vanadium
9
Microstructure
Optical microscope
To be sure our observation consider grains in all dimensions
Side
Top
Different agents used to reveal the grains:
 Nital 3%
 Picral
 Valeila
 Kalling
 Specific agent (90 ml boiling distilled water, 10 g picric acid, Two drops of Zephiran
chloride) which proposed by “Mokhtar Ben Salah” Master student of ETS
10
Microstructure
 Nital, Picral, Valeila and Kalling are not reveal grains
boundary
The pictures below show sample that etched by Nital3%
500X
1000X
Etched by Nital3%
11
Microstructure
Specific agent
 Keep in 60 °C (to avoid crystallization
of picric)
 Etching time: 60s
No difference between
grains in specimen Top and
Side
Grains are not stretched
Top
Side
12
Conclusion
 In material composition vanadium added by manufacturer for
a special purpose.
Precipitate the vanadium-rich carbides
 Refining of grain growth austenite
 Further structure also will be fine
 Increase strength and toughness
13
Etched by Kaling
Conclusion
Possible applications:
Plastic injection molds(https://www.youtube.com/watch?v=eOr-lpny13U)
Compression molds
 Rubbers
 Fibre glass renforcements
 Composites,…
14
Conclusion
Grains are not stretched
Cold roll
Casting
15
Hot roll
Forge
Conclusion
Sample hardness: 33HRC
P20 Usually quenched and tempered
Proposed range for tempering of AISI P20 is 480̊C to 595
Tempered in >600̊C or long term(maybe sample part from core)
16
Ref:Chandler, H., Heat Treater's Guide: Practices and Procedures for Irons and Steels. 1994: ASM International
Thanks for all your attentions
Questions/Comments?
17