PSI - Issue 47

Irina A. Bannikova et al. / Procedia Structural Integrity 47 (2023) 602–607 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

605

4

1000

Quartz No.1_0.51 GPa_QSL Quartzite No.3_0.028 GPa_DL

N t = 27.08 t imp R² = 0.95

-0.43

100

N t = -8.88 ln(t imp ) + 31.26 R² = 0.98

N t = -25.29 ln(t imp ) + 14.67 R² = 0.97

N t = 56.23 t imp R² = 0.99

-0.64

N t

10

1

0.01

0.1

1

10

100

1000

t imp , μ s

Fig. 3. Quartz (no.1) and quartzite (no.3) cylinders test data. Cumulative distributions of the number of time intervals (N t ) greater than some specified from time intervals (t imp ) between pulses of the entire signal of fractoluminescence by PMT.

Quartzite cylinders were deformed into two types of fragments with characteristic sizes (1.6

a

b

Sandstone_0.288 GPa

Quartzite No.1_0.34 GPa_QSL

100000000

1000000

N all = 0.93 m R² = 0.95

N all = 2.24 m R² = 0.93

-0.77

-1.01

100000

II

1000000

10000

2

1000

10000

N

N small = 8.5 m R² = 0.91

-0.90

N

N small = 1.09 m R² = 0.96

-0.75

100

I

1

100

10

N big = 0.69 m R² = 0.98

-1.42

N big = 16.50 e

-10.98 m

R² = 0.96

1

1

0.0000001 0.00001

0.001

0.1

0.0000001 0.00001

0.001

0.1

m, g

m, g

Fig. 4. Cumulative fragment size(mass) distributions (a) for sample from sandstone by DL and (b) for sample from quartzite by QSL. Logarithmic axes.

In the case of fracture of tubular aluminum oxide samples, two types of fragments were observed: fragments comparable with the size of the sample (2D fragments with characteristic size is equal or larger than tube thickness, d*≥d T ) and volumetric small fragments (3D) (Fig. 5a). It is shown that the inflection points in the cumulative distributions of fragments by mass shifted toward smaller scales when the loading energy density increased (see Fig. 2).