Tension–tension cyclic fatigue tests (triangular waveform, σmax = 100 MPa, R = 0.1) were conducted on hot isostatically pressed (HIPed) silicon nitride at frequencies spanning several orders of magnitude (5.6 × 10−6 to 0.1 Hz or 10−3 MPa/s to 18 MPa/s) at 1370°C in air. The amount of cyclic creep strain was found to be a function of the frequency or stressing rate, with greater strains to failure observed as the frequency or stressing rate decreased. The total strain was viewed as the sum of elastic, anelastic (or transient recoverable), and plastic (viscous or nonrecoverable) strain contributions, after the empirical Pao and Marin model. The plastic strain was found to be the dominant component of the total creep and was unsatisfactorily represented by the Pao and Marin model. To circumvent this, a time exponent was introduced in the plastic strain term in the Pao and Marin model. This modification resulted in good correlation between model and experiment at the slower frequencies examined but overpredicted the cyclic creep strain at the faster frequencies. The utility of using the modified Pao and Marin model to predict cyclic creep response from static creep and strain relaxation tests is described.

Issue Section:
Gas Turbines: Ceramics
Topics:
Creep, Silicon nitride ceramics, Tension, Failure, Fatigue testing, Relaxation (Physics), Transients (Dynamics)
1.
Andrade
E. N. da C.
,
1914
, “
The Viscous Flow in Metals and Allied Phenomena
,”
Proc. Roy. Soc.
, Vol.
A90
, p.
329
329
.
2.
Arons
R. M.
, and
Tien
J. K.
,
1980
, “
Creep and Strain Recovery in Hot-Pressed Silicon Nitride
,”
J. Mat. Sci.
, Vol.
15
, pp.
2046
–
2058
.
3.
Ding
J.-L.
,
Liu
K. C.
,
More
K. L.
, and
Brinkman
C. R.
,
1994
, “
Creep and Creep Rupture of an Advanced Silicon Nitride Ceramic
,”
J. Am. Cer. Soc.
, Vol.
77
, No.
4
, pp.
867
–
874
.
4.
Ferber
M. K.
, and
Jenkins
M. G.
,
1992
, “
Evaluation of the Strength and Creep-Fatigue Behavior of Hot Isostatically Pressed Silicon Nitride
,”
J. Am. Cer. Soc.
, Vol.
75
, No.
9
, pp.
2453
–
2462
.
5.
Kraus, H., 1980, Creep Analysis, Wiley, New York.
6.
Lange
F. F.
,
Clarke
D. R.
, and
Davis
B. I.
,
1980
, “
Compressive Creep of Si3N4/MgO Alloys, Part 2, Source of Viscoelastic Effect
,”
J. Mat. Sci.
, Vol.
15
, pp.
611
–
615
.
7.
Lin
C.-K. J.
,
Jenkins
M. G.
, and
Ferber
M. K.
,
1993
, “
Tensile Dynamic and Static Fatigue Relations for a HIPed Silicon Nitride at Elevated Temperatures
,”
J. Eur. Cer. Soc.
, Vol.
12
, pp.
3
–
13
.
8.
Lin
C.-K. J.
,
Jenkins
M. G.
, and
Ferber
M. K.
,
1994
, “
Cyclic Fatigue of Hot Isostatically Pressed Silicon Nitride at Elevated Temperatures
,”
J. Mat. Sci.
, Vol.
29
, pp.
3517
–
3526
.
9.
Liu, K. C., and Brinkman, C. R., 1987, “Dynamic Tensile Cyclic Fatigue of Si3N4,” Proc. of the 25th Automotive Technology Development Contractors’ Coordination Meeting, P-209, pp. 189–197.
10.
Lubahn
J. D.
,
1953
, “
The Role of Anelasticity in Creep, Tension, and Relaxation Behavior
,”
Trans, of the A. S. M.
, Vol.
45
, pp.
787
–
838
.
11.
Luecke, W., Wiederhorn, S. M., Hockey, B. J., and Long, G. G., 1993, Silicon Nitride Ceramics, V287, Mat. Res. Soc. Symp. Proc, I.-W. Chen et al., eds., pp. 467–72.
12.
Menon
M. N.
,
Fang
H. T.
,
Wu
D. C.
,
Jenkins
M. G.
,
Ferber
M. K.
,
More
K. L.
,
Hubbard
C. R.
, and
Nolan
T. A.
,
1994
, “
Creep and Stress Rupture Behavior of an Advanced Silicon Nitride: Part 1, Experimental Observations
,”
J. Am. Cer. Soc.
, Vol.
77
, No.
5
, pp.
1217
–
27
.
13.
Ohji
T.
,
Sakai
S.
,
Ito
M.
,
Yamauchi
Y.
,
Kanematsu
W.
, and
Ito
S.
,
1987
, “
Yielding Phenomena of Hot-Pressed Si3N4
,”
High Temperature Technology
, Vol.
5
, pp.
139
–
144
.
14.
Pao, Y.-H., and Marin, J., 1953, “An Analytical Theory of the Creep Deformation of Materials,” J. Appl. Mech., No. 6, pp. 245–252.
15.
Wereszczak
A. A.
,
Kirkland
T. P.
, and
Ferber
M. K.
,
1994
, “
Stress and Strain Relaxation Behaviour in HIPed Silicon Nitrides
,”
J. Mat. Sci. Lett.
, Vol.
13
, pp.
1469
–
71
.
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