Reliability and life prediction of ceramic composite structures at elevated temperatures

In this research, conjugated thermal and fluid dynamics simulations are presented on a modern hollow clay slab blocks filled pre-stressed reinforced concrete beam slab construction. The simulation parameters were set from Eurocode standards and calibrated using data from standardized fire tests of the same slab construction. We evaluated the temperature distributions of the slabs under transient conditions against standard fire load. Knowing the temperature distribution against time at certain points of the structure, the loss of load bearing capacity of the structure is definable at elevated temperatures. The results demonstrated that we could pre-establish the thermal behavior of complex composite structures exposed to fire using thermal and CFD simulation tools. Our results and method of fire resistance tests can contribute to fire safety planning of buildings.

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Fiber Composite Strength Modeling With Extension to Life Prediction

Journal of Engineering Materials and Technology ◽

10.1115/1.2128424 ◽

2005 ◽

Vol 128 (1) ◽

pp. 41-49

Author(s):

Edward M. Wu ◽

John L. Kardos

Keyword(s):

Composite Structures ◽

Life Prediction ◽

Failure Modes ◽

Fiber Composite ◽

Probability Model ◽

Load Sharing ◽

Local Load ◽

Statistical Parameters ◽

Composite Strength ◽

Fiber Manufacturing

This paper focuses on the probability modeling of fiber composite strength, wherein the failure modes are dominated by fiber tensile failures. The probability model is the tri-modal local load-sharing model, which is the Phoenix-Harlow local load-sharing model with the filament failure model extended from one mode to three modes. This model results in increased efficiency in the determination of fiber statistical parameters and in lower cost when applied to (i) quality control in materials (fiber) manufacturing, (ii) materials (fiber) selection and comparison, (iii) accounting for the effect of size scaling in design, and (iv) qualification and certification of critical composite structures that are too large and expensive to test statistically. In addition, possible extensions to proof testing and time-dependent life prediction are discussed and preliminary data are presented.

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Compressive creep behavior of an oxide–oxide ceramic composite with monazite fiber coating at elevated temperatures

Materials Science and Engineering A ◽

10.1016/j.msea.2006.11.131 ◽

2007 ◽

Vol 454-455 ◽

pp. 590-601 ◽

Cited By ~ 19

Author(s):

P.R. Jackson ◽

M.B. Ruggles-Wrenn ◽

S.S. Baek ◽

K.A. Keller

Keyword(s):

Creep Behavior ◽

Ceramic Composite ◽

Elevated Temperatures ◽

Oxide Ceramic ◽

Compressive Creep ◽

Fiber Coating

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A Study on Mechanical and Tribological Properties of Hot Pressed Al2O3/ZrO2/h-BN/TiO2 Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.695.417 ◽

2011 ◽

Vol 695 ◽

pp. 417-420 ◽

Cited By ~ 1

Author(s):

Hyun Hwi Lee ◽

Seung Ho Kim ◽

Bhupendra Joshi ◽

Soo Wohn Lee

Keyword(s):

Tribological Properties ◽

Ceramic Composite ◽

Elevated Temperatures ◽

Cutting Tools ◽

High Hardness ◽

High Melting Point ◽

Corrosion Resistant ◽

Mechanical And Tribological Properties ◽

Chemical Inertness ◽

Corrosion Resistant Coatings

Oxide ceramics such as alumina and zirconia are industrially utilized as cutting tools, a variety of bearings, biomaterials, and thermal and corrosion-resistant coatings due to their high hardness, chemical inertness, high melting point, and ability to retain mechanical strength at elevated temperatures. In this research, the effect of other ceramic additives (TiO2) and h-BN within alumina(α-Al2O3) and yttria-stabilized tetragonal (Y-TZP) composite was studied with respect to the mechanical and tribological properties. The lowest coefficient of frction of 0.45 was observed for the ZTA ceramic composite with hBN-TiO2. The highest hardness, fracture toughness and flexural strength were obtained as 15.7GPa, 5.2MPam-1/2, 712MPa, respectively.

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Validation of Inelastic Analysis by Full-Scale Component Testing

Journal of Pressure Vessel Technology ◽

10.1115/1.3264854 ◽

1987 ◽

Vol 109 (1) ◽

pp. 42-49 ◽

Cited By ~ 2

Author(s):

D. S. Griffin ◽

A. K. Dhalla ◽

W. S. Woodward

Keyword(s):

Life Prediction ◽

Elevated Temperatures ◽

Full Scale ◽

Prediction Methods ◽

Material Models ◽

Component Testing ◽

Inelastic Analysis ◽

Creep Buckling ◽

Design Requirements ◽

Thermal Striping

This paper compares theoretical and experimental results for full-scale, prototypical components tested at elevated-temperatures to provide validation for inelastic analysis methods, material models, and design limits. Results are discussed for piping elbow plastic and creep buckling, creep ratcheting, and creep relaxation; nozzle creep ratcheting and weld cracking; and thermal striping fatigue. Comparisons between theory and test confirm the adequacy of components to meet design requirements, but identify specific areas where life prediction methods could be made more precise.

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