Coercivity, saturation magnetisation and Size dependent properties of Nano particles Magnetic hysteresis Magnetic induction field lags behinds Magnetic field intensity Hysteresis loop If an alternating magneric field is applied to the material it’s magnetic induction will traceout a loop called HYSTERESIS LOOP Saturation of magnetization Increase in applied external magnetic field (H) cannot increase the magnetization of material further Retentivity of magnetization Remaining magnetization when external magnetic field (H) Co-ercivity of magnetization Magnetization (B) =0 for negative to the external magnetic field (H) Size dependent properties of nano particles SIZE plays vital role on the mechanical properties Plastic deformation of nanostructure coating strictly depends on the grain size With decrease in grain size beyond certain limit, Hall-Petch eqn doesn’t apply this indicates particular material will become softer Reduction of granule size has remarkable effect on improvement of resistant against erosion in nanostructure and composite materials Erosion behavior under low and average loading condition in nano-materials shows that , because of higher stiffness, erosion resistance of these materials is more than that of materials with large size. Effect of size on Mechanical properties It is differ from conventional or bulk structures Effective elastic properties of these small-scale structural elements strongly depends on their size. Small-scale structures are very sensitive to the micro-structural features of the material such as the GRAIN SIZE , the finite NUMBER OF GRAINS ,BOUNDARY LAYER THICKNESS , TEXTURE and DISLOCATION STRUCTURE . Research studies have shown that when particles ‘ size reaches to the dimension of nanometer , remarkable improvement can be observed in strength of composites In nanoscale bars and plates effective elastic properties of structural elements strongly depend on their size It was found that a nano-whisker can have a mechanical strength approaching to the theoretical strength values Strength increase becomes appreciable only on diameter less than 10microns thanks

1. CONCEPT OF CO-ERCIVITY & SATURATION OF
MAGNETISATION
BY
ESWARAN MURUGESAN
17PCH003
1

2. MAGNETIC HYSTERESIS
Magnetic induction
field lags behinds
Magnetic field intensity
2

3. Saturation of magnetization
Increase in applied external magnetic field (H) cannot increase the magnetization of material further
Retentivity of magnetization
Remaining magnetization when external magnetic field (H)
Co-ercivity of magnetization
Magnetization (B) =0 for negative to the external magnetic field (H)
Hysteresis loop
If an alternating magneric field is applied to the material it’s magnetic induction will traceout a
loop called HYSTERESIS LOOP
3

4. WHY SPECIPICALLY FERRO MAGNETIC
MATERIAL
• EXTREME form paramagnet -these are sponteneously magnetized
4

5. DOMAINS OF
FERROMATERIALS
5

6. 4 CONDITIONS OF
HYSTERESIS1. Magnetic dipole prefers always LINE UP
2. Net magetisim = 0
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7. 3. Energy if Domain opposite to H
Energy if Domain parallal to H
4. Domain Boundaries can shift
Let take a iron rod which is
surrounded by sellinoid n turns wire
this connected with DC Battery
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8. 8

9. APPLYING THISPHENOMENONON NANOSCALE
• By Using nanomaterials of ferromagnetics
• Working in very efficient way and residual magnetism gets high life
• This is termed to be possible way of MANUFACTURING
NANOBATTERIES,COMPUTER CHIPS…ETC
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10. SIZE DEPENDENT
PROPERTIES OF NANO
PARTICLES
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11. INTRODUCTION
• SIZE plays vital role on the mechanical properties
• Plastic deformation of nanostructure coating strictly depends on the
grain size
• With decrease in grain size beyond certain limit, Hall-Petch eqn doesn’t
apply
this indicates particular material will become softer
• Reduction of granule size has remarkable effect on improvement of
resistant against erosion in nanostructure and composite materials
• Erosion behavior under low and average loading condition in nano-
materials shows that , because of higher stiffness, erosion resistance of
these materials is more than that of materials with large size
11

12. EFFECT OF SIZE ON MECHANICAL
PROPERTIES
• It is differ from conventional or bulk structures
• Effective elastic properties of these small-scale structural
elements strongly depends on their size.
• Small-scale structures are very sensitive to the micro-
structural features of the material such as the GRAIN SIZE ,
the finite NUMBER OF GRAINS ,BOUNDARY LAYER THICKNESS
, TEXTURE and DISLOCATION STRUCTURE .
• Research studies have shown that when particles ‘ size
reaches to the dimension of nanometer , remarkable
improvement can be observed in strength of composites
12

13. •In nanoscale bars and plates effective elastic
properties of structural elements strongly depend on
their size
•It was found that a nano-whisker can have a
mechanical strength approaching to the theoretical
strength values
•Strength increase becomes appreciable only on
diameter less than 10microns
13

14. HALL-PETCH EQUATION
14

15. HARDNESS , TENSILE , STRAIN 15

16. 16

17. •thanks
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