Potential Applications of Structural Ceramic Composites in Gas Turbines

Parks, W. P.; Ramey, R. R.; Rawlins, D. C.; Price, Jeffrey R.; Roode, Mark van

doi:10.1115/90-gt-251

Cited by 3 publications

(3 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These goals can be achieved in part through reductions in the amount of film cooling of combustor liners and turbine airfoils with attendant increases in the temperatures both within the gas turbine and at the burner outlet. 1,2 In current gas turbine engines, many of the superalloy-based components are operating at or near their upper use temperature, even with the benefits imparted by the use of thermal barrier coatings, thereby precluding significant temperature elevations with these alloys. To meet future environmental and performance standards, it is anticipated that the targeted temperature elevations in turbine components will be accomplished through the use of continuous-fiber-reinforced ceramic composites (CFCCs).…”

Section: Introductionmentioning

confidence: 99%

Effects of Thermal Aging on the Mechanical Properties of a Porous‐Matrix Ceramic Composite

Carelli

Fujita

Yang

et al. 2002

Journal of the American Ceramic Society

View full text Add to dashboard Cite

The present article focuses on changes in the mechanical properties of an all-oxide fiber-reinforced composite following long-term exposure (1000 h) at temperatures of 1000 -1200°C in air. The composite of interest derives its damage tolerance from a highly porous matrix, precluding the need for an interphase at the fiber-matrix boundary. The key issue involves the stability of the porosity against densification and the associated implications for long-term durability of the composite at elevated temperatures. For this purpose, comparisons are made in the tensile properties and fracture characteristics of a 2D woven fiber composite both along the fiber direction and at 45°to the fiber axes before and after the aging treatments. Additionally, changes in the state of the matrix are probed through measurements of matrix hardness by Vickers indentation and through the determination of the matrix Young's modulus, using the measured composite moduli coupled with classical laminate theory. The study reveals that, despite evidence of some strengthening of the matrix and the fiber-matrix interfaces during aging, the key tensile properties in the 0°/90°orientation, including strength and failure strain, are unchanged. This strengthening is manifested to a more significant extent in the composite properties in the ؎45°o rientation, wherein the modulus and the tensile strength each exhibit a twofold increase after the 1200°C aging treatment. It also results in a change in the failure mechanism, from one involving predominantly matrix damage and interply delamination to one which is dominated by fiber fracture. Additionally, salient changes in the mechanical response beyond the maximum load suggest the existence of an optimum matrix strength at which the fracture energy in the ؎45°orientation attains a maximum. The implications for long-term durability of this class of composite are discussed.

show abstract

Section: Introductionmentioning

confidence: 99%

Effects of Thermal Aging on the Mechanical Properties of a Porous‐Matrix Ceramic Composite

Carelli

Fujita

Yang

et al. 2002

Journal of the American Ceramic Society

View full text Add to dashboard Cite

show abstract

“…Nowadays, composite materials have an important industrial and technological development. The manufacturer's capability to achieve the desired properties and behaviors is enhanced by combining two or more different materials; however, the final properties are not necessarily between those of pure materials [1][2][3][4][5][6]. In the manufacture of structural ceramics, the composite ceramic-ceramic strategy has been used for decades [5,[7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Low (and negative) thermal expansion Al2TiO5 materials and Al2TiO5 - 3Al2O3.2SiO2 - ZrTiO4 composite materials. Processing, initial zircon proportion effect, and properties

Violini

Hernández

Gauna

et al. 2018

Ceramics International

View full text Add to dashboard Cite

Aluminum titanate (Al 2 TiO 5) materials and aluminum titanate-mullite-zirconium titanate (Al 2 TiO 5-3Al 2 O 3 .2SiO 2-ZrTiO 4) composite materials were successfully processed from fine commercial powders and characterized. This was achieved by zircon (ZrSiO 4) addition to stoichiometric alumina-titania mixtures. Zircon addition was the principal processing variable explored. This additive stabilizes the unstable aluminum titanate phase, enhances the sintering process, restricts microcrack development and improves the mechanical properties of the bulk material, but has a slight detrimental effect on its thermal expansion behavior (α app from-1.5 to 2.5 x 10-6 °C-1 in the RT-800 °C range). With a clear microstructure configuration change, all the technological properties are directly (linearly) correlated with zircon proportion in the initial formulation in the range between 5 and 30 wt%. Developed phases were established, relatively dense ceramics were produced, and complex microstructures with multiphasic interlocked grains were identified. Also, an interconnected microcrack matrix was observed with no material integrity loss which explained the low or even negative thermal expansion behaviors observed in the developed materials. This, together with the mechanical behavior detected, encourages structural applications with high thermomechanical solicitations. The triplex composite material presented an excellent thermomechanical behavior and low porosity, 48 MPa flexural strength, low stiffness and high sintering grade with low thermal expansion.

show abstract

“…During the last decade, important efforts have resulted in significant advances in structural materials and analysis. To achieve such advances, developments in high temperature materials, like ceramic composites, are considered key for potential use in turbine rotor blades, nozzle vanes (Parks et.al., 1991), rocket engines and space structures (Upadhya, 1992). Therefore, fiber-reinforced ceramic matrix composites are receiving increased attention (Tan et.al., 1991 andMah et.a.1., 1987) owing to their high-temperature capabilities (Abdullah and Das-Gupta, 1990) and the toughening properties provided by the fibrous reinforcement (Mall et.al., 1985).…”

Section: Introductionmentioning

confidence: 99%

Analysis of the Temperature Profile of Ceramic Composite Materials Exposed to Combined Conduction-Radiation Between Concentric Cylinders

Tremante

Malpica

1997

Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation;

View full text Add to dashboard Cite

A numerical study is made of the thermal characteristics of semitransparent materials exposed to simultaneous conduction and radiation between concentric cylinders. For extremely high-temperature applications, where radiative transfer plays an important role, ceramic-matrix composites, considered as semitransparent materials, are being explored for potential use in turbines and compressors components, spacecraft structures, engine control systems and nuclear reactors. Through the use of a gray model and the the two flux method, specialized equations are developed that generate a system of nonlinear ordinary differential equations. To facilitate the solution of this system, an iterative strategy is adopted. In order to demonstrate the versatility and accuracy of the proposed methodology, the results of several numerical experiments are presented and compared with benchmark solutions.

show abstract

Potential Applications of Structural Ceramic Composites in Gas Turbines

Cited by 3 publications

References 11 publications

Effects of Thermal Aging on the Mechanical Properties of a Porous‐Matrix Ceramic Composite

Effects of Thermal Aging on the Mechanical Properties of a Porous‐Matrix Ceramic Composite

Low (and negative) thermal expansion Al2TiO5 materials and Al2TiO5 - 3Al2O3.2SiO2 - ZrTiO4 composite materials. Processing, initial zircon proportion effect, and properties

Analysis of the Temperature Profile of Ceramic Composite Materials Exposed to Combined Conduction-Radiation Between Concentric Cylinders

Contact Info

Product

Resources

About