Mixed-mode fracture of structural ceramics under a biaxial stress state was investigated by an anticlastic bending test using the controlled surface flaw technique. The stress state of the anticlastic bending specimen is biaxial. This test enables the study of fractures under pure mode I, pure mode II, or any combination of mode I and mode II loading. To discuss the experimental results, a parameter “T” was introduced to the modified maximum hoop stress criterion. This parameter represents frictional effects of crack interfaces on the mixed-mode fracture and can be obtained experimentally. Relative magnitudes of mode I and mode II stress intensity factors and the directions of non-coplanar crack extension angles were predicted using the parameter “T.” Reasonable agreement with the experimental results was obtained.

Issue Section:
Gas Turbines: Ceramics
Topics:
Ceramics, Fracture toughness, Stress, Fracture (Materials), Fracture (Process), Friction, Hoop stress
1.
Chiang, W. T., 1977, “Fracture Criteria for Combined Mode Cracks,” Fracture 4, pp. 135–154.
2.
Eftis
J.
, and
Subramonian
N.
,
1978
, “
The Inclined Crack Under Biaxial Load
,”
Eng. Fract. Mech.
, Vol.
10
, pp.
43
–
67
.
3.
Erdogan
F.
, and
Sih
G. C.
,
1963
, “
On the Crack Extension in Plates Under Plane Loading and Transverse Shear
,”
ASME Journal of Basic Engineering
, Vol.
85
, pp.
519
–
527
.
4.
Hayashi
S.
,
Suzuki
A.
, and
Sugiyama
S.
,
1991
,
Transactions of Japan Society of Mechanical Engineers
, Vol.
57
, No.
534
, pp.
298
–
302
[in Japanese].
5.
Hussain, M. A., Pu, S. L., and Underwood, J., 1974, “Strain Energy Release Rate for a Crack Under Combined Mode I and Mode II,” Fracture Analyses, ASTM STP 560, pp. 2–28.
6.
Ichikawa
M.
, and
Tanaka
S.
,
1982
, “
A Critical Analysis of the Relationship Between the Energy Release Rate and the Stress Intensity Factors for Non-coplanar Crack Extension Under Combined Mode Loading
,”
International Journal of Fracture
, Vol.
18
, pp.
19
–
28
.
7.
Marshall
D. B.
,
1984
, “
Mechanics of Failure From Surface Flaws in Mixed-Mode Loading
,”
Journal Am. Ceram. Soc.
, Vol.
67
, No.
2
, pp.
110
–
116
.
8.
Miyoshi, T., Sagawa, N., and Sassa, T., 1985, Transactions of Japan Society of Mechanical Engineers, Vol. 51, No. 471 [in Japanese].
9.
Newman, J. C., and Raju, I. S., 1979, “Analyses of Surface Cracks in Finite Plates Under Tension or Bending Loads,” NASA Technical Paper 1578.
10.
Ohji
K.
,
1967
,
Journal of Material Science of Japan
, Vol.
16
, pp.
213
–
21
[in Japanese].
11.
Ono
T.
,
Takenoshita
T.
,
Uchimura
H.
, and
Kaji
M.
,
1993
,
Journal of Ceramics Society of Japan
, Vol.
101
, No.
2
, pp.
240
–
243
[in Japanese].
12.
Palaniswamy
K.
, and
Knauss
W. G.
,
1978
, “
On the Problem of Crack Extension in Brittle Solids Under General Loading
,”
Mechanics Today
, Vol.
4
, pp.
87
–
148
.
13.
Petrovic, J. J., and Mediratta, M. G., 1977, “Correction of Mixed-Mode Fracture From Controlled Surface Flaws in Hot-Pressed Si3N4,” J. Am. Ceram. Soc., Vol. 60, No. 9.
14.
Shetty
D. K.
,
Rosenfield
A. R.
, and
Duckworth
W. H.
,
1986
, “
Mixed-Mode Fracture of Ceramics in Diametral Compression
,”
J. Am. Ceram. Soc.
, Vol.
69
, No.
6
, pp.
437
–
443
.
15.
Shetty
D. K.
,
Rosenfield
A. R.
, and
Duckworth
W. H.
,
1987
, “
Mixed-Mode Fracture in Biaxial Stress State: Application of the Diametral-Compression (Brazilian Disk) Test
,”
Eng. Fract. Mech.
, Vol.
26
, No.
6
, pp.
825
–
840
.
16.
Shetty
D. K.
,
1987
, “
Mixed-Mode Fracture Criteria for Reliability Analysis and Design with Structural Ceramics
,”
ASME JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER
, Vol.
109
, pp.
282
–
289
.
17.
Sih
G. C.
,
1974
, “
Strain-Energy-Density Factor Applied to Mixed-Mode Crack Problems
,”
International Journal of Fracture
, Vol.
10
, pp.
305
–
321
.
18.
Smith, F. W., and Sorensen, D. R., 1974, “Mixed-Mode Stress Intensity Factors for Semielliptical Surface Cracks,” NASA CR-134684.
This content is only available via PDF.
Copyright © 1997
 by The American Society of Mechanical Engineers
You do not currently have access to this content.