G. Kaupp, M. R. Naimi-Jamal Powerpoint Presentation, ECM22 Budapest, August 26-31, 2004

G. Kaupp, M. R. Naimi-Jamal

Powerpoint Presentation, ECM22

Budapest, August 26-31, 2004

0-FN 0-FN

constant FN

constant FL

nanoindentation ramp nanoscratching constant load nanoscratching(indent, hold FN , and scratch)

0-FL

G. Kaupp, M. R. Naimi-Jamal, ECM22, Budapest, August 26-31, 2004

Nanoindentation and Nanoscratching

Mechanical properties of crystals and solids

Indentation hardness (with respect to projected contact area) Young`s elastic modulus Elasticity/plasticity Nanoindentation coefficient [µN/nm3/2] Work of the nanoindentation Phase transitions (pressure induced) Long-range effects Face anisotropies ____________________________________________________ Abrasion/pileup Scratch coefficient [1/µN1/2] (instead of “friction coefficient”) Scratch work Scratch resistance Phase transitions (pressure induced) Angle and face dependence Anisotropic molecular migrations Relation to crystal structure and chemical reactivity


Al-Berkovich

loading: FN = k h3/2 k [µN/nm3/2] = indentation coefficient


Al, Conosphere (R=1µm)y = 0,1812x + 109,72

0

2000

4000

6000

8000

10000

12000

0 20000 40000 60000

(norm. displ.)1,5 (nm)1.5

no

rmal

fo

rce

(µN

)

0

2000

4000

6000

8000

10000

12000

0 1000000 2000000

(norm. displ.)2 (nm)2

no

rmal

fo

rce

(µN

)

The relation of normal force and normal displacement FN = k·h3/2 (k [µN/nm3/2] = indentation coefficient)


0

1000

2000

3000

4000

5000

6000

0 1000 2000 3000

(norm. displ.)1.5 (nm1.5)

no

rmal

fo

rce (

µN

)

Quartz (10-10)

0

500

1000

1500

2000

2500

3000

0 250 500 750 1000(norm. displ.)1.5 (nm1.5)

no

rmal

fo

rce

(µN

)

SrTiO3 (110)

cubic SrTiO3(Pm-3m); tetragonal (I4/mcm) ?trigonal -quartzmonoclinic coesite (>2.2 GPa)tetragonal stishovite (>8.2 GPa)

Crystalline SiO2 and SrTiO3


k1 = 0.058 µN/nm3/2

Cube corner:

k2 = 0.0188 µN/nm3/2

WN tot tg = 11.27 µNµm (100 µN)

Anthracene, coefficients and work of indentation


Isotropic and anisotropic indentation responce

Far-reaching phenomena with crystals


Cube corner nanoindentation of α-quartz (P3221) up to 5000 µN; Berkovich nanoindentation of strontium titanate (Pm-3m) up to 3000 µN load.

Compd. Face hmax

(nm) H

(Gpa) Er

(Gpa) k1

(µNnm-3/2) k2

(µNnm-3/2) Wp/We WNtot tgα

(µNµm) SiO2 (10-10) 201 15.3 109.0 1.956 1.590 1.07 420.8 SiO2 (01-10) 191 16.2 119.7 2.145 1.728 1.09 378.3 SiO2 (01-11) 179 17.4 133.6 2.730 1.844 1.26 379.1 SiO2 (10-11) 193 16.5 105.0 2.256 1.668 1.17 404.7 SiO2 (1-100) 193 16.6 109.4 2.303 1.656 1.05 395.6

SrTiO3 (100) 102 11.7 236 2.754 3.536 1.53 329.7 SrTiO3 (110) 103 12.0 254 2.462 3.390 2.04 331.1 SrTiO3 (111) 102 11.1 246 2.317 3.096 2.08 355.7

Face anisotropy in nanoindentations


Appearances of nanoscratches by AFM

ramp experiment constant normal force

Z range 50 nm


y = 0,1926x - 44,289

0

50

100

150

200

250

0 300 600 900 1200 1500

normal force (μN)

late

ral f

orce

(μN)

y = 0,0046x + 0,022

0

50

100

150

200

250

0 10000 20000 30000 40000 50000

normal force1.5 (μN1.5)

late

ral f

orce

(μN)

y = 0,0001x + 21,791

0

50

100

150

200

250

0 500000 1000000 1500000 2000000

normal force2 (μN2)

late

ral f

orce

(μN)

(a) (b) (c)normal force (µN) (normal force)1.5 (µN1.5) (normal force)2 (µN2)

FL = K·FN3/2 (K = scratch coefficient [N-1/2])

Linear plot through the origin only with exponent 1.5 (not 1 or 2)

The relation of lateral force and (fixed) normal force

Fused quartz and cube corner indentation tip, edge in front

The value for the lateral force gives the scratch work [µNµm] for 1 µm scratch length


exponent 1.5 (not 1 or 2)the steep line in (b) corresponds to phase transformed SrTiO3

0

100

200

300

0 20000 40000 60000

(normal force)1.5 (µN1.5 )

late

ral

forc

e (

µN

)

y1 = 0,0047x1 + 3,8443

y2 = 0,0071x 2 - 61,218

0

100

200

300

0 500 1000 1500

normal force (µN)

late

ral

forc

e (

µN

)

(a) (b)

y = 0,0048x + 13,571

0

40

80

120

160

200

0 10000 20000 30000 40000

late

ral

forc

e (

µN

)

(c)

y = 0,0001x + 33,419

0

40

80

120

160

200

0 250000 500000 750000 1000000

(normal force)2 (µN 2)

late

ral

forc

e (

µN

)

(d)invalid

(normal force)1.5 (µN1.5)acceptable

The relation of lateral force and (fixed) normal forceSrTiO3 (100), 0°, cube corner edge in front


SrTiO3 (100) SrTiO3 (110) SrTiO3 (111)

Spec. scratch work (3 µm, 60 s, FN = 1190 µN ) Angle µNµm 0° 246.6 45° 270.1 90° 240.4



Angular and facial dependence of specific scratch work on strontium titanate at different normal loads (WSc, spec = FL

.1 [µNµm])


Angular dependence of specific scratch work on (1-100) of -quartz and crystal packing

(1-100), scratch work per µm scratch length (FN=1482 µN):

Angle µNµm

90° 206 45° 223 0° 225

spec.WSc = FL.1 [µNµm] = work for 1 µm scratch length of the indented tip

c-direction: alternation of 0.5405nm Si-Si rows; the other directions are less distant and the skew (10-11) cleavage plane is cutting in c-direction


NH

NH

O S

Molecular migrations under (110) of thiohydantoin

(P21/c)

(a) 0° (b) 90° (c) 180° (d) 270°


cleavage planes between steep (66°) monolayers

Geometric model for the understanding of the marked anisotropies upon scratching over skew cleavage planes in four orthogonal directions

Reason for the orientational specifity on (110) of thiohydantoin

In all directions: FL = K.FN3/2 is valid


Nanoscratching of anthracene on (110)

(110) on top


ramp nanoscratching at 0-150 µN on (001)

(001) on topanthracene

Nanoscratching on the layers


Tetraphenylethene (P21) on (10-1)

Poor vertical (010) cleavage planes between monolayers of bulky molecules


OH

OH

O

O

Cube corner scratches on ninhydrin (110) along the polar axis

edge in front

side in front

Nanoscratching along the polar axis of ninhydrin

180°

180°

180°

(P21)


(image rotated by 10° around x and y)

Thiourea, anisotropic nanoscratching on (100)

ab

c

(100)

ramp nanoscratching at 0-150 µN

b) along [001] (c)

a) along [010] (b)

S

NH2 NH2

(Pbnm)


G. Kaupp, M. R. Naimi-Jamal Powerpoint Presentation, ECM22 Budapest, August 26-31, 2004

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Transcript of G. Kaupp, M. R. Naimi-Jamal Powerpoint Presentation, ECM22 Budapest, August 26-31, 2004